diff --git a/app/main/__init__.py b/app/main/__init__.py
index 2a6bff976..6d431a63a 100644
--- a/app/main/__init__.py
+++ b/app/main/__init__.py
@@ -29,6 +29,7 @@ from app.main.views import (  # noqa
     find_users,
     platform_admin,
     email_branding,
+    letter_branding,
     conversation,
     organisations,
     notifications,
diff --git a/app/main/forms.py b/app/main/forms.py
index 52aeffb41..4cc423401 100644
--- a/app/main/forms.py
+++ b/app/main/forms.py
@@ -851,6 +851,21 @@ class ServiceUpdateEmailBranding(StripWhitespaceForm):
             raise ValidationError('This field is required')
 
 
+class SVGFileUpload(StripWhitespaceForm):
+    file = FileField_wtf(
+        'Upload an SVG logo',
+        validators=[
+            FileAllowed(['svg'], 'SVG Images only!'),
+            DataRequired(message="You need to upload a file to submit")
+        ]
+    )
+
+
+class ServiceLetterBrandingDetails(StripWhitespaceForm):
+    name = StringField('Name of brand', validators=[DataRequired()])
+    domain = GovernmentDomainField('Domain')
+
+
 class PDFUploadForm(StripWhitespaceForm):
     file = FileField_wtf(
         'Upload a letter in PDF format to check if it fits in the printable area',
diff --git a/app/main/s3_client.py b/app/main/s3_client.py
deleted file mode 100644
index 5fc79c6f2..000000000
--- a/app/main/s3_client.py
+++ /dev/null
@@ -1,144 +0,0 @@
-import uuid
-
-import botocore
-from boto3 import resource
-from flask import current_app
-from notifications_utils.s3 import s3upload as utils_s3upload
-
-FILE_LOCATION_STRUCTURE = 'service-{}-notify/{}.csv'
-TEMP_TAG = 'temp-{user_id}_'
-LOGO_LOCATION_STRUCTURE = '{temp}{unique_id}-{filename}'
-
-
-def get_s3_object(bucket_name, filename):
-    s3 = resource('s3')
-    return s3.Object(bucket_name, filename)
-
-
-def get_csv_location(service_id, upload_id):
-    return (
-        current_app.config['CSV_UPLOAD_BUCKET_NAME'],
-        FILE_LOCATION_STRUCTURE.format(service_id, upload_id),
-    )
-
-
-def get_csv_upload(service_id, upload_id):
-    return get_s3_object(*get_csv_location(service_id, upload_id))
-
-
-def delete_s3_object(filename):
-    bucket_name = current_app.config['LOGO_UPLOAD_BUCKET_NAME']
-    get_s3_object(bucket_name, filename).delete()
-
-
-def persist_logo(old_name, new_name):
-    if old_name == new_name:
-        return
-    bucket_name = current_app.config['LOGO_UPLOAD_BUCKET_NAME']
-    get_s3_object(bucket_name, new_name).copy_from(
-        CopySource='{}/{}'.format(bucket_name, old_name))
-    delete_s3_object(old_name)
-
-
-def get_s3_objects_filter_by_prefix(prefix):
-    bucket_name = current_app.config['LOGO_UPLOAD_BUCKET_NAME']
-    s3 = resource('s3')
-    return s3.Bucket(bucket_name).objects.filter(Prefix=prefix)
-
-
-def get_temp_truncated_filename(filename, user_id):
-    return filename[len(TEMP_TAG.format(user_id=user_id)):]
-
-
-def s3upload(service_id, filedata, region):
-    upload_id = str(uuid.uuid4())
-    bucket_name, file_location = get_csv_location(service_id, upload_id)
-    utils_s3upload(
-        filedata=filedata['data'],
-        region=region,
-        bucket_name=bucket_name,
-        file_location=file_location,
-    )
-    return upload_id
-
-
-def s3download(service_id, upload_id):
-    contents = ''
-    try:
-        key = get_csv_upload(service_id, upload_id)
-        contents = key.get()['Body'].read().decode('utf-8')
-    except botocore.exceptions.ClientError as e:
-        current_app.logger.error("Unable to download s3 file {}".format(
-            FILE_LOCATION_STRUCTURE.format(service_id, upload_id)))
-        raise e
-    return contents
-
-
-def get_mou(organisation_is_crown):
-    bucket = current_app.config['MOU_BUCKET_NAME']
-    filename = 'crown.pdf' if organisation_is_crown else 'non-crown.pdf'
-    attachment_filename = 'GOV.UK Notify data sharing and financial agreement{}.pdf'.format(
-        '' if organisation_is_crown else ' (non-crown)'
-    )
-    try:
-        key = get_s3_object(bucket, filename)
-        return {
-            'filename_or_fp': key.get()['Body'],
-            'attachment_filename': attachment_filename,
-            'as_attachment': True,
-        }
-    except botocore.exceptions.ClientError as exception:
-        current_app.logger.error("Unable to download s3 file {}/{}".format(
-            bucket, filename
-        ))
-        raise exception
-
-
-def upload_logo(filename, filedata, region, user_id):
-    upload_file_name = LOGO_LOCATION_STRUCTURE.format(
-        temp=TEMP_TAG.format(user_id=user_id),
-        unique_id=str(uuid.uuid4()),
-        filename=filename
-    )
-    bucket_name = current_app.config['LOGO_UPLOAD_BUCKET_NAME']
-    utils_s3upload(
-        filedata=filedata,
-        region=region,
-        bucket_name=bucket_name,
-        file_location=upload_file_name,
-        content_type='image/png'
-    )
-
-    return upload_file_name
-
-
-def permanent_logo_name(filename, user_id):
-    if filename.startswith(TEMP_TAG.format(user_id=user_id)):
-        return get_temp_truncated_filename(filename=filename, user_id=user_id)
-    else:
-        return filename
-
-
-def delete_temp_files_created_by(user_id):
-    for obj in get_s3_objects_filter_by_prefix(TEMP_TAG.format(user_id=user_id)):
-        delete_s3_object(obj.key)
-
-
-def delete_temp_file(filename):
-    if not filename.startswith(TEMP_TAG[:5]):
-        raise ValueError('Not a temp file: {}'.format(filename))
-
-    delete_s3_object(filename)
-
-
-def set_metadata_on_csv_upload(service_id, upload_id, **kwargs):
-    get_csv_upload(
-        service_id, upload_id
-    ).copy_from(
-        CopySource='{}/{}'.format(*get_csv_location(service_id, upload_id)),
-        ServerSideEncryption='AES256',
-        Metadata={
-            key: str(value) for key, value in kwargs.items()
-        },
-        MetadataDirective='REPLACE',
-    )
diff --git a/app/main/views/agreement.py b/app/main/views/agreement.py
index b3e41dbb5..3862be01c 100644
--- a/app/main/views/agreement.py
+++ b/app/main/views/agreement.py
@@ -2,8 +2,8 @@ from flask import abort, render_template, request, send_file, url_for
 from flask_login import login_required
 
 from app.main import main
-from app.main.s3_client import get_mou
 from app.main.views.sub_navigation_dictionaries import features_nav
+from app.s3_client.s3_mou_client import get_mou
 from app.utils import AgreementInfo
 
 
diff --git a/app/main/views/email_branding.py b/app/main/views/email_branding.py
index 5a5b3f9a4..338de3c77 100644
--- a/app/main/views/email_branding.py
+++ b/app/main/views/email_branding.py
@@ -4,13 +4,13 @@ from flask_login import login_required
 from app import email_branding_client
 from app.main import main
 from app.main.forms import SearchTemplatesForm, ServiceUpdateEmailBranding
-from app.main.s3_client import (
+from app.s3_client.s3_logo_client import (
     TEMP_TAG,
-    delete_temp_file,
-    delete_temp_files_created_by,
-    permanent_logo_name,
+    delete_email_temp_file,
+    delete_email_temp_files_created_by,
+    permanent_email_logo_name,
     persist_logo,
-    upload_logo,
+    upload_email_logo,
 )
 from app.utils import AgreementInfo, get_logo_cdn_domain, user_is_platform_admin
 
@@ -49,7 +49,7 @@ def update_email_branding(branding_id, logo=None):
 
     if form.validate_on_submit():
         if form.file.data:
-            upload_filename = upload_logo(
+            upload_filename = upload_email_logo(
                 form.file.data.filename,
                 form.file.data,
                 current_app.config['AWS_REGION'],
@@ -57,11 +57,11 @@ def update_email_branding(branding_id, logo=None):
             )
 
             if logo and logo.startswith(TEMP_TAG.format(user_id=session['user_id'])):
-                delete_temp_file(logo)
+                delete_email_temp_file(logo)
 
             return redirect(url_for('.update_email_branding', branding_id=branding_id, logo=upload_filename))
 
-        updated_logo_name = permanent_logo_name(logo, session["user_id"]) if logo else None
+        updated_logo_name = permanent_email_logo_name(logo, session["user_id"]) if logo else None
 
         email_branding_client.update_email_branding(
             branding_id=branding_id,
@@ -76,7 +76,7 @@ def update_email_branding(branding_id, logo=None):
         if logo:
             persist_logo(logo, updated_logo_name)
 
-        delete_temp_files_created_by(session["user_id"])
+        delete_email_temp_files_created_by(session["user_id"])
 
         return redirect(url_for('.email_branding', branding_id=branding_id))
 
@@ -98,7 +98,7 @@ def create_email_branding(logo=None):
 
     if form.validate_on_submit():
         if form.file.data:
-            upload_filename = upload_logo(
+            upload_filename = upload_email_logo(
                 form.file.data.filename,
                 form.file.data,
                 current_app.config['AWS_REGION'],
@@ -106,11 +106,11 @@ def create_email_branding(logo=None):
             )
 
             if logo and logo.startswith(TEMP_TAG.format(user_id=session['user_id'])):
-                delete_temp_file(logo)
+                delete_email_temp_file(logo)
 
             return redirect(url_for('.create_email_branding', logo=upload_filename))
 
-        updated_logo_name = permanent_logo_name(logo, session["user_id"]) if logo else None
+        updated_logo_name = permanent_email_logo_name(logo, session["user_id"]) if logo else None
 
         email_branding_client.create_email_branding(
             logo=updated_logo_name,
@@ -124,7 +124,7 @@ def create_email_branding(logo=None):
         if logo:
             persist_logo(logo, updated_logo_name)
 
-        delete_temp_files_created_by(session["user_id"])
+        delete_email_temp_files_created_by(session["user_id"])
 
         return redirect(url_for('.email_branding'))
 
diff --git a/app/main/views/letter_branding.py b/app/main/views/letter_branding.py
new file mode 100644
index 000000000..ec6630548
--- /dev/null
+++ b/app/main/views/letter_branding.py
@@ -0,0 +1,116 @@
+from flask import (
+    current_app,
+    redirect,
+    render_template,
+    request,
+    session,
+    url_for,
+)
+from flask_login import login_required
+from notifications_python_client.errors import HTTPError
+from requests import get as requests_get
+
+from app import letter_branding_client
+from app.main import main
+from app.main.forms import ServiceLetterBrandingDetails, SVGFileUpload
+from app.s3_client.s3_logo_client import (
+    LETTER_TEMP_TAG,
+    delete_letter_temp_file,
+    delete_letter_temp_files_created_by,
+    get_letter_filename_with_no_path_or_extension,
+    letter_filename_for_db,
+    permanent_letter_logo_name,
+    persist_logo,
+    upload_letter_png_logo,
+    upload_letter_temp_logo,
+)
+from app.utils import get_logo_cdn_domain, user_is_platform_admin
+
+
+@main.route("/letter-branding/create", methods=['GET', 'POST'])
+@main.route("/letter-branding/create/<path:logo>", methods=['GET', 'POST'])
+@login_required
+@user_is_platform_admin
+def create_letter_branding(logo=None):
+    file_upload_form = SVGFileUpload()
+    letter_branding_details_form = ServiceLetterBrandingDetails()
+
+    file_upload_form_submitted = file_upload_form.file.data
+    details_form_submitted = request.form.get('operation') == 'branding-details'
+
+    if file_upload_form_submitted and file_upload_form.validate_on_submit():
+        upload_filename = upload_letter_temp_logo(
+            file_upload_form.file.data.filename,
+            file_upload_form.file.data,
+            current_app.config['AWS_REGION'],
+            user_id=session["user_id"]
+        )
+
+        if logo and logo.startswith(LETTER_TEMP_TAG.format(user_id=session['user_id'])):
+            delete_letter_temp_file(logo)
+
+        return redirect(url_for('.create_letter_branding', logo=upload_filename))
+
+    if details_form_submitted and letter_branding_details_form.validate_on_submit():
+        if logo:
+            db_filename = letter_filename_for_db(logo, session['user_id'])
+            png_file = get_png_file_from_svg(logo)
+
+            try:
+                letter_branding_client.create_letter_branding(
+                    filename=db_filename,
+                    name=letter_branding_details_form.name.data,
+                    domain=letter_branding_details_form.domain.data,
+                )
+
+                upload_letter_logos(logo, db_filename, png_file, session['user_id'])
+
+                # TODO: redirect to all letter branding page once it exists
+                return redirect(url_for('main.platform_admin'))
+
+            except HTTPError as e:
+                if 'domain' in e.message:
+                    letter_branding_details_form.domain.errors.append(e.message['domain'][0])
+                elif 'name' in e.message:
+                    letter_branding_details_form.name.errors.append(e.message['name'][0])
+                else:
+                    raise e
+        else:
+            # Show error on upload form if trying to submit with no logo
+            file_upload_form.validate()
+
+    return render_template(
+        'views/letter-branding/manage-letter-branding.html',
+        file_upload_form=file_upload_form,
+        letter_branding_details_form=letter_branding_details_form,
+        cdn_url=get_logo_cdn_domain(),
+        logo=logo
+    )
+
+
+def get_png_file_from_svg(filename):
+    filename_for_template_preview = get_letter_filename_with_no_path_or_extension(filename)
+
+    template_preview_svg_endpoint = '{}/{}.svg.png'.format(
+        current_app.config['TEMPLATE_PREVIEW_API_HOST'],
+        filename_for_template_preview
+    )
+
+    response = requests_get(
+        template_preview_svg_endpoint,
+        headers={'Authorization': 'Token {}'.format(current_app.config['TEMPLATE_PREVIEW_API_KEY'])}
+    )
+
+    return response.content
+
+
+def upload_letter_logos(old_filename, new_filename, png_file, user_id):
+    persist_logo(old_filename, permanent_letter_logo_name(new_filename, 'svg'))
+
+    upload_letter_png_logo(
+        permanent_letter_logo_name(new_filename, 'png'),
+        png_file,
+        current_app.config['AWS_REGION'],
+    )
+
+    delete_letter_temp_files_created_by(user_id)
diff --git a/app/main/views/send.py b/app/main/views/send.py
index c85280185..e61dd8935 100644
--- a/app/main/views/send.py
+++ b/app/main/views/send.py
@@ -42,7 +42,11 @@ from app.main.forms import (
     SetSenderForm,
     get_placeholder_form_instance,
 )
-from app.main.s3_client import s3download, s3upload, set_metadata_on_csv_upload
+from app.s3_client.s3_csv_client import (
+    s3download,
+    s3upload,
+    set_metadata_on_csv_upload,
+)
 from app.template_previews import TemplatePreview, get_page_count_for_letter
 from app.utils import (
     Spreadsheet,
diff --git a/app/navigation.py b/app/navigation.py
index 05e43e9f2..f784360fe 100644
--- a/app/navigation.py
+++ b/app/navigation.py
@@ -75,6 +75,7 @@ class HeaderNavigation(Navigation):
         'platform-admin': {
             'add_organisation',
             'create_email_branding',
+            'create_letter_branding',
             'email_branding',
             'find_users_by_email',
             'live_services',
@@ -405,6 +406,7 @@ class MainNavigation(Navigation):
         'conversation_updates',
         'cookies',
         'create_email_branding',
+        'create_letter_branding',
         'data_retention',
         'delete_template_folder',
         'delivery_and_failure',
@@ -583,6 +585,7 @@ class CaseworkNavigation(Navigation):
         'copy_template',
         'create_api_key',
         'create_email_branding',
+        'create_letter_branding',
         'data_retention',
         'delete_service_template',
         'delete_template_folder',
@@ -817,6 +820,7 @@ class OrgNavigation(Navigation):
         'copy_template',
         'create_api_key',
         'create_email_branding',
+        'create_letter_branding',
         'data_retention',
         'delete_service_template',
         'delete_template_folder',
diff --git a/app/notify_client/letter_branding_client.py b/app/notify_client/letter_branding_client.py
index 96a0889dc..84ab0b80f 100644
--- a/app/notify_client/letter_branding_client.py
+++ b/app/notify_client/letter_branding_client.py
@@ -6,5 +6,13 @@ class LetterBrandingClient(NotifyAdminAPIClient):
     def get_letter_branding(self):
         return self.get(url='/dvla_organisations')
 
+    def create_letter_branding(self, filename, name, domain):
+        data = {
+            "filename": filename,
+            "name": name,
+            "domain": domain,
+        }
+        return self.post(url="/letter-branding", data=data)
+
 
 letter_branding_client = LetterBrandingClient()
diff --git a/app/s3_client/__init__.py b/app/s3_client/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/app/s3_client/s3_csv_client.py b/app/s3_client/s3_csv_client.py
new file mode 100644
index 000000000..f9d0b5b9f
--- /dev/null
+++ b/app/s3_client/s3_csv_client.py
@@ -0,0 +1,57 @@
+import uuid
+
+import botocore
+from flask import current_app
+from notifications_utils.s3 import s3upload as utils_s3upload
+
+from app.s3_client.s3_logo_client import get_s3_object
+
+FILE_LOCATION_STRUCTURE = 'service-{}-notify/{}.csv'
+
+
+def get_csv_location(service_id, upload_id):
+    return (
+        current_app.config['CSV_UPLOAD_BUCKET_NAME'],
+        FILE_LOCATION_STRUCTURE.format(service_id, upload_id),
+    )
+
+
+def get_csv_upload(service_id, upload_id):
+    return get_s3_object(*get_csv_location(service_id, upload_id))
+
+
+def s3upload(service_id, filedata, region):
+    upload_id = str(uuid.uuid4())
+    bucket_name, file_location = get_csv_location(service_id, upload_id)
+    utils_s3upload(
+        filedata=filedata['data'],
+        region=region,
+        bucket_name=bucket_name,
+        file_location=file_location,
+    )
+    return upload_id
+
+
+def s3download(service_id, upload_id):
+    contents = ''
+    try:
+        key = get_csv_upload(service_id, upload_id)
+        contents = key.get()['Body'].read().decode('utf-8')
+    except botocore.exceptions.ClientError as e:
+        current_app.logger.error("Unable to download s3 file {}".format(
+            FILE_LOCATION_STRUCTURE.format(service_id, upload_id)))
+        raise e
+    return contents
+
+
+def set_metadata_on_csv_upload(service_id, upload_id, **kwargs):
+    get_csv_upload(
+        service_id, upload_id
+    ).copy_from(
+        CopySource='{}/{}'.format(*get_csv_location(service_id, upload_id)),
+        ServerSideEncryption='AES256',
+        Metadata={
+            key: str(value) for key, value in kwargs.items()
+        },
+        MetadataDirective='REPLACE',
+    )
diff --git a/app/s3_client/s3_logo_client.py b/app/s3_client/s3_logo_client.py
new file mode 100644
index 000000000..bb8626bae
--- /dev/null
+++ b/app/s3_client/s3_logo_client.py
@@ -0,0 +1,135 @@
+import uuid
+
+from boto3 import resource
+from flask import current_app
+from notifications_utils.s3 import s3upload as utils_s3upload
+
+TEMP_TAG = 'temp-{user_id}_'
+EMAIL_LOGO_LOCATION_STRUCTURE = '{temp}{unique_id}-{filename}'
+LETTER_PREFIX = 'letters/static/images/letter-template/'
+LETTER_TEMP_TAG = LETTER_PREFIX + TEMP_TAG
+LETTER_TEMP_LOGO_LOCATION = 'letters/static/images/letter-template/temp-{user_id}_{unique_id}-{filename}'
+
+
+def get_s3_object(bucket_name, filename):
+    s3 = resource('s3')
+    return s3.Object(bucket_name, filename)
+
+
+def delete_s3_object(filename):
+    bucket_name = current_app.config['LOGO_UPLOAD_BUCKET_NAME']
+    get_s3_object(bucket_name, filename).delete()
+
+
+def persist_logo(old_name, new_name):
+    if old_name == new_name:
+        return
+    bucket_name = current_app.config['LOGO_UPLOAD_BUCKET_NAME']
+    get_s3_object(bucket_name, new_name).copy_from(
+        CopySource='{}/{}'.format(bucket_name, old_name))
+    delete_s3_object(old_name)
+
+
+def get_s3_objects_filter_by_prefix(prefix):
+    bucket_name = current_app.config['LOGO_UPLOAD_BUCKET_NAME']
+    s3 = resource('s3')
+    return s3.Bucket(bucket_name).objects.filter(Prefix=prefix)
+
+
+def get_temp_truncated_filename(filename, user_id):
+    return filename[len(TEMP_TAG.format(user_id=user_id)):]
+
+
+def get_letter_filename_with_no_path_or_extension(filename):
+    return filename[len(LETTER_PREFIX):-4]
+
+
+def upload_email_logo(filename, filedata, region, user_id):
+    upload_file_name = EMAIL_LOGO_LOCATION_STRUCTURE.format(
+        temp=TEMP_TAG.format(user_id=user_id),
+        unique_id=str(uuid.uuid4()),
+        filename=filename
+    )
+    bucket_name = current_app.config['LOGO_UPLOAD_BUCKET_NAME']
+    utils_s3upload(
+        filedata=filedata,
+        region=region,
+        bucket_name=bucket_name,
+        file_location=upload_file_name,
+        content_type='image/png'
+    )
+
+    return upload_file_name
+
+
+def upload_letter_temp_logo(filename, filedata, region, user_id):
+    upload_filename = LETTER_TEMP_LOGO_LOCATION.format(
+        user_id=user_id,
+        unique_id=str(uuid.uuid4()),
+        filename=filename
+    )
+    bucket_name = current_app.config['LOGO_UPLOAD_BUCKET_NAME']
+    utils_s3upload(
+        filedata=filedata,
+        region=region,
+        bucket_name=bucket_name,
+        file_location=upload_filename,
+        content_type='image/svg+xml'
+    )
+
+    return upload_filename
+
+
+def upload_letter_png_logo(filename, filedata, region):
+    bucket_name = current_app.config['LOGO_UPLOAD_BUCKET_NAME']
+    utils_s3upload(
+        filedata=filedata,
+        region=region,
+        bucket_name=bucket_name,
+        file_location=filename,
+        content_type='image/png'
+    )
+
+
+def permanent_email_logo_name(filename, user_id):
+    if filename.startswith(TEMP_TAG.format(user_id=user_id)):
+        return get_temp_truncated_filename(filename=filename, user_id=user_id)
+    else:
+        return filename
+
+
+def permanent_letter_logo_name(filename, extension):
+    return LETTER_PREFIX + filename + '.' + extension
+
+
+def letter_filename_for_db(filename, user_id):
+    filename = get_letter_filename_with_no_path_or_extension(filename)
+
+    if filename.startswith(TEMP_TAG.format(user_id=user_id)):
+        filename = get_temp_truncated_filename(filename=filename, user_id=user_id)
+
+    return filename
+
+
+def delete_email_temp_files_created_by(user_id):
+    for obj in get_s3_objects_filter_by_prefix(TEMP_TAG.format(user_id=user_id)):
+        delete_s3_object(obj.key)
+
+
+def delete_letter_temp_files_created_by(user_id):
+    for obj in get_s3_objects_filter_by_prefix(LETTER_TEMP_TAG.format(user_id=user_id)):
+        delete_s3_object(obj.key)
+
+
+def delete_email_temp_file(filename):
+    if not filename.startswith(TEMP_TAG[:5]):
+        raise ValueError('Not a temp file: {}'.format(filename))
+
+    delete_s3_object(filename)
+
+
+def delete_letter_temp_file(filename):
+    if not filename.startswith(LETTER_TEMP_TAG[:43]):
+        raise ValueError('Not a temp file: {}'.format(filename))
+
+    delete_s3_object(filename)
diff --git a/app/s3_client/s3_mou_client.py b/app/s3_client/s3_mou_client.py
new file mode 100644
index 000000000..d86e7b2cc
--- /dev/null
+++ b/app/s3_client/s3_mou_client.py
@@ -0,0 +1,24 @@
+import botocore
+from flask import current_app
+
+from app.s3_client.s3_logo_client import get_s3_object
+
+
+def get_mou(organisation_is_crown):
+    bucket = current_app.config['MOU_BUCKET_NAME']
+    filename = 'crown.pdf' if organisation_is_crown else 'non-crown.pdf'
+    attachment_filename = 'GOV.UK Notify data sharing and financial agreement{}.pdf'.format(
+        '' if organisation_is_crown else ' (non-crown)'
+    )
+    try:
+        key = get_s3_object(bucket, filename)
+        return {
+            'filename_or_fp': key.get()['Body'],
+            'attachment_filename': attachment_filename,
+            'as_attachment': True,
+        }
+    except botocore.exceptions.ClientError as exception:
+        current_app.logger.error("Unable to download s3 file {}/{}".format(
+            bucket, filename
+        ))
+        raise exception
diff --git a/app/templates/views/letter-branding/manage-letter-branding.html b/app/templates/views/letter-branding/manage-letter-branding.html
new file mode 100644
index 000000000..060054208
--- /dev/null
+++ b/app/templates/views/letter-branding/manage-letter-branding.html
@@ -0,0 +1,37 @@
+{% extends "views/platform-admin/_base_template.html" %}
+{% from "components/file-upload.html" import file_upload %}
+{% from "components/page-footer.html" import page_footer %}
+{% from "components/textbox.html" import textbox %}
+{% from "components/form.html" import form_wrapper %}
+
+{% block per_page_title %}
+  Create letter branding
+{% endblock %}
+
+{% block platform_admin_content %}
+
+  <h1 class="heading-large">Add letter branding</h1>
+  <div class="grid-row">
+    <div class="column-three-quarters">
+      {% if logo %}
+        <div id="logo-img">
+          <img src="https://{{ cdn_url }}/{{ logo }}"/>
+        </div>
+      {% endif %}
+      {{ file_upload(file_upload_form.file) }}
+      {% call form_wrapper() %}
+        <div class="form-group">
+          <div style='margin-top:15px;'>{{textbox(letter_branding_details_form.name)}}</div>
+          <div style='margin-top:15px;'>{{textbox(letter_branding_details_form.domain)}}</div>
+          {{ page_footer(
+            'Save',
+            button_name='operation',
+            button_value='branding-details',
+            back_link=url_for('main.platform_admin'),
+            back_link_text='Back to letter branding selection',
+          ) }}
+        </div>
+      {% endcall %}
+    </div>
+
+{% endblock %}
diff --git a/app/utils.py b/app/utils.py
index 0f7ee1134..c7ed47090 100644
--- a/app/utils.py
+++ b/app/utils.py
@@ -126,7 +126,7 @@ def get_errors_for_csv(recipients, template_type):
 
 def generate_notifications_csv(**kwargs):
     from app import notification_api_client
-    from app.main.s3_client import s3download
+    from app.s3_client.s3_csv_client import s3download
     if 'page' not in kwargs:
         kwargs['page'] = 1
 
diff --git a/tests/app/main/test_s3_client.py b/tests/app/main/test_s3_client.py
deleted file mode 100644
index 20c6d80a3..000000000
--- a/tests/app/main/test_s3_client.py
+++ /dev/null
@@ -1,130 +0,0 @@
-from collections import namedtuple
-from unittest.mock import Mock, call
-
-import pytest
-
-from app.main.s3_client import (
-    LOGO_LOCATION_STRUCTURE,
-    TEMP_TAG,
-    delete_temp_file,
-    delete_temp_files_created_by,
-    permanent_logo_name,
-    persist_logo,
-    set_metadata_on_csv_upload,
-    upload_logo,
-)
-
-bucket = 'test_bucket'
-data = {'data': 'some_data'}
-filename = 'test.png'
-upload_id = 'test_uuid'
-region = 'eu-west1'
-
-
-@pytest.fixture
-def upload_filename(fake_uuid):
-    return LOGO_LOCATION_STRUCTURE.format(
-        temp=TEMP_TAG.format(user_id=fake_uuid), unique_id=upload_id, filename=filename)
-
-
-def test_upload_logo_calls_correct_args(client, mocker, fake_uuid, upload_filename):
-    mocker.patch('uuid.uuid4', return_value=upload_id)
-    mocker.patch.dict('flask.current_app.config', {'LOGO_UPLOAD_BUCKET_NAME': bucket})
-    mocked_s3_upload = mocker.patch('app.main.s3_client.utils_s3upload')
-
-    upload_logo(filename=filename, user_id=fake_uuid, filedata=data, region=region)
-
-    assert mocked_s3_upload.called_once_with(
-        filedata=data,
-        region=region,
-        file_location=upload_filename,
-        bucket_name=bucket
-    )
-
-
-def test_persist_logo(client, mocker, fake_uuid, upload_filename):
-    mocker.patch.dict('flask.current_app.config', {'LOGO_UPLOAD_BUCKET_NAME': bucket})
-    mocked_get_s3_object = mocker.patch('app.main.s3_client.get_s3_object')
-    mocked_delete_s3_object = mocker.patch('app.main.s3_client.delete_s3_object')
-
-    new_filename = permanent_logo_name(upload_filename, fake_uuid)
-
-    persist_logo(upload_filename, new_filename)
-
-    assert mocked_get_s3_object.called_once_with(bucket, new_filename)
-    assert mocked_delete_s3_object.called_once_with(bucket, upload_filename)
-
-
-def test_persist_logo_returns_if_not_temp(client, mocker, fake_uuid):
-    filename = 'logo.png'
-    persist_logo(filename, filename)
-
-    mocked_get_s3_object = mocker.patch('app.main.s3_client.get_s3_object')
-    mocked_delete_s3_object = mocker.patch('app.main.s3_client.delete_s3_object')
-
-    mocked_get_s3_object.assert_not_called()
-    mocked_delete_s3_object.assert_not_called()
-
-
-def test_permanent_logo_name_removes_temp_tag_from_filename(upload_filename, fake_uuid):
-    new_name = permanent_logo_name(upload_filename, fake_uuid)
-
-    assert new_name == 'test_uuid-test.png'
-
-
-def test_permanent_logo_name_does_not_change_filenames_with_no_temp_tag():
-    filename = 'logo.png'
-    new_name = permanent_logo_name(filename, filename)
-
-    assert new_name == filename
-
-
-def test_delete_temp_files_created_by_user(client, mocker, fake_uuid):
-    obj = namedtuple("obj", ["key"])
-    objs = [obj(key='test1'), obj(key='test2')]
-
-    mocker.patch('app.main.s3_client.get_s3_objects_filter_by_prefix', return_value=objs)
-    mocked_delete_s3_object = mocker.patch('app.main.s3_client.delete_s3_object')
-
-    delete_temp_files_created_by(fake_uuid)
-
-    assert mocked_delete_s3_object.called_with_args(objs[0].key)
-    for index, arg in enumerate(mocked_delete_s3_object.call_args_list):
-        assert arg == call(objs[index].key)
-
-
-def test_delete_single_temp_file(client, mocker, fake_uuid, upload_filename):
-    mocked_delete_s3_object = mocker.patch('app.main.s3_client.delete_s3_object')
-
-    delete_temp_file(upload_filename)
-
-    assert mocked_delete_s3_object.called_with_args(upload_filename)
-
-
-def test_does_not_delete_non_temp_file(client, mocker, fake_uuid):
-    filename = 'logo.png'
-    mocked_delete_s3_object = mocker.patch('app.main.s3_client.delete_s3_object')
-
-    with pytest.raises(ValueError) as error:
-        delete_temp_file(filename)
-
-    assert mocked_delete_s3_object.called_with_args(filename)
-    assert str(error.value) == 'Not a temp file: {}'.format(filename)
-
-
-def test_sets_metadata(client, mocker):
-    mocked_s3_object = Mock()
-    mocked_get_s3_object = mocker.patch(
-        'app.main.s3_client.get_csv_upload',
-        return_value=mocked_s3_object,
-    )
-
-    set_metadata_on_csv_upload('1234', '5678', foo='bar', baz=True)
-
-    mocked_get_s3_object.assert_called_once_with('1234', '5678')
-    mocked_s3_object.copy_from.assert_called_once_with(
-        CopySource='test-notifications-csv-upload/service-1234-notify/5678.csv',
-        Metadata={'baz': 'True', 'foo': 'bar'},
-        MetadataDirective='REPLACE',
-        ServerSideEncryption='AES256',
-    )
diff --git a/tests/app/main/views/test_agreement.py b/tests/app/main/views/test_agreement.py
index 02bc6b34e..8da0fd3e2 100644
--- a/tests/app/main/views/test_agreement.py
+++ b/tests/app/main/views/test_agreement.py
@@ -78,7 +78,7 @@ def test_downloading_agreement(
     expected_file_served,
 ):
     mock_get_s3_object = mocker.patch(
-        'app.main.s3_client.get_s3_object',
+        'app.s3_client.s3_mou_client.get_s3_object',
         return_value=_MockS3Object(b'foo')
     )
     user = active_user_with_permissions(fake_uuid)
@@ -100,7 +100,7 @@ def test_agreement_cant_be_downloaded_unknown_crown_status(
     fake_uuid,
 ):
     mock_get_s3_object = mocker.patch(
-        'app.main.s3_client.get_s3_object',
+        'app.s3_client.s3_mou_client.get_s3_object',
         return_value=_MockS3Object()
     )
     user = active_user_with_permissions(fake_uuid)
@@ -116,7 +116,7 @@ def test_agreement_requires_login(
     mocker,
 ):
     mock_get_s3_object = mocker.patch(
-        'app.main.s3_client.get_s3_object',
+        'app.s3_client.s3_mou_client.get_s3_object',
         return_value=_MockS3Object()
     )
     response = client.get(url_for('main.download_agreement'))
@@ -142,7 +142,7 @@ def test_show_public_agreement_page(
     expected_status,
 ):
     mocker.patch(
-        'app.main.s3_client.get_s3_object',
+        'app.s3_client.s3_mou_client.get_s3_object',
         return_value=_MockS3Object()
     )
     response = client.get(url_for(
diff --git a/tests/app/main/views/test_email_branding.py b/tests/app/main/views/test_email_branding.py
index 6b8d1f318..be702a3bd 100644
--- a/tests/app/main/views/test_email_branding.py
+++ b/tests/app/main/views/test_email_branding.py
@@ -6,7 +6,7 @@ from bs4 import BeautifulSoup
 from flask import url_for
 from notifications_python_client.errors import HTTPError
 
-from app.main.s3_client import LOGO_LOCATION_STRUCTURE, TEMP_TAG
+from app.s3_client.s3_logo_client import EMAIL_LOGO_LOCATION_STRUCTURE, TEMP_TAG
 from tests.conftest import (
     mock_get_email_branding,
     normalize_spaces,
@@ -114,7 +114,7 @@ def test_create_new_email_branding_without_logo(
     }
 
     mock_persist = mocker.patch('app.main.views.email_branding.persist_logo')
-    mocker.patch('app.main.views.email_branding.delete_temp_files_created_by')
+    mocker.patch('app.main.views.email_branding.delete_email_temp_files_created_by')
 
     logged_in_platform_admin_client.post(
         url_for('.create_email_branding'),
@@ -141,7 +141,7 @@ def test_cant_create_new_email_branding_with_unknown_domain(
     mock_create_email_branding
 ):
     mock_persist = mocker.patch('app.main.views.email_branding.persist_logo')
-    mocker.patch('app.main.views.email_branding.delete_temp_files_created_by')
+    mocker.patch('app.main.views.email_branding.delete_email_temp_files_created_by')
 
     client_request.login(platform_admin_user(fake_uuid))
     page = client_request.post(
@@ -197,7 +197,7 @@ def test_rejects_non_canonical_domain_when_adding_email_branding(
     expected_error,
 ):
     mocker.patch('app.main.views.email_branding.persist_logo')
-    mocker.patch('app.main.views.email_branding.delete_temp_files_created_by')
+    mocker.patch('app.main.views.email_branding.delete_email_temp_files_created_by')
     data = {
         'logo': None,
         'colour': '#ff0000',
@@ -225,7 +225,7 @@ def test_create_email_branding_requires_a_name_when_submitting_logo_details(
     mock_create_email_branding,
 ):
     mocker.patch('app.main.views.email_branding.persist_logo')
-    mocker.patch('app.main.views.email_branding.delete_temp_files_created_by')
+    mocker.patch('app.main.views.email_branding.delete_email_temp_files_created_by')
     data = {
         'operation': 'email-branding-details',
         'logo': '',
@@ -252,7 +252,7 @@ def test_create_email_branding_does_not_require_a_name_when_uploading_a_file(
     mocker,
     fake_uuid,
 ):
-    mocker.patch('app.main.views.email_branding.upload_logo', return_value='temp_filename')
+    mocker.patch('app.main.views.email_branding.upload_email_logo', return_value='temp_filename')
     data = {
         'file': (BytesIO(''.encode('utf-8')), 'test.png'),
         'colour': '',
@@ -290,14 +290,14 @@ def test_create_new_email_branding_when_branding_saved(
         'brand_type': 'org_banner'
     }
 
-    temp_filename = LOGO_LOCATION_STRUCTURE.format(
+    temp_filename = EMAIL_LOGO_LOCATION_STRUCTURE.format(
         temp=TEMP_TAG.format(user_id=user_id),
         unique_id=fake_uuid,
         filename=data['logo']
     )
 
     mocker.patch('app.main.views.email_branding.persist_logo')
-    mocker.patch('app.main.views.email_branding.delete_temp_files_created_by')
+    mocker.patch('app.main.views.email_branding.delete_email_temp_files_created_by')
 
     logged_in_platform_admin_client.post(
         url_for('.create_email_branding', logo=temp_filename),
@@ -342,24 +342,24 @@ def test_deletes_previous_temp_logo_after_uploading_logo(
     with logged_in_platform_admin_client.session_transaction() as session:
         user_id = session["user_id"]
 
-    temp_old_filename = LOGO_LOCATION_STRUCTURE.format(
+    temp_old_filename = EMAIL_LOGO_LOCATION_STRUCTURE.format(
         temp=TEMP_TAG.format(user_id=user_id),
         unique_id=fake_uuid,
         filename='old_test.png'
     )
 
-    temp_filename = LOGO_LOCATION_STRUCTURE.format(
+    temp_filename = EMAIL_LOGO_LOCATION_STRUCTURE.format(
         temp=TEMP_TAG.format(user_id=user_id),
         unique_id=fake_uuid,
         filename='test.png'
     )
 
-    mocked_upload_logo = mocker.patch(
-        'app.main.views.email_branding.upload_logo',
+    mocked_upload_email_logo = mocker.patch(
+        'app.main.views.email_branding.upload_email_logo',
         return_value=temp_filename
     )
 
-    mocked_delete_temp_file = mocker.patch('app.main.views.email_branding.delete_temp_file')
+    mocked_delete_email_temp_file = mocker.patch('app.main.views.email_branding.delete_email_temp_file')
 
     logged_in_platform_admin_client.post(
         url_for('main.create_email_branding', logo=temp_old_filename, branding_id=fake_uuid),
@@ -367,9 +367,9 @@ def test_deletes_previous_temp_logo_after_uploading_logo(
         content_type='multipart/form-data'
     )
 
-    assert mocked_upload_logo.called
-    assert mocked_delete_temp_file.called
-    assert mocked_delete_temp_file.call_args == call(temp_old_filename)
+    assert mocked_upload_email_logo.called
+    assert mocked_delete_email_temp_file.called
+    assert mocked_delete_email_temp_file.call_args == call(temp_old_filename)
 
 
 def test_update_existing_branding(
@@ -391,14 +391,14 @@ def test_update_existing_branding(
         'brand_type': 'both'
     }
 
-    temp_filename = LOGO_LOCATION_STRUCTURE.format(
+    temp_filename = EMAIL_LOGO_LOCATION_STRUCTURE.format(
         temp=TEMP_TAG.format(user_id=user_id),
         unique_id=fake_uuid,
         filename=data['logo']
     )
 
     mocker.patch('app.main.views.email_branding.persist_logo')
-    mocker.patch('app.main.views.email_branding.delete_temp_files_created_by')
+    mocker.patch('app.main.views.email_branding.delete_email_temp_files_created_by')
 
     logged_in_platform_admin_client.post(
         url_for('.update_email_branding', logo=temp_filename, branding_id=fake_uuid),
@@ -431,14 +431,14 @@ def test_temp_logo_is_shown_after_uploading_logo(
     with logged_in_platform_admin_client.session_transaction() as session:
         user_id = session["user_id"]
 
-    temp_filename = LOGO_LOCATION_STRUCTURE.format(
+    temp_filename = EMAIL_LOGO_LOCATION_STRUCTURE.format(
         temp=TEMP_TAG.format(user_id=user_id),
         unique_id=fake_uuid,
         filename='test.png'
     )
 
-    mocker.patch('app.main.views.email_branding.upload_logo', return_value=temp_filename)
-    mocker.patch('app.main.views.email_branding.delete_temp_file')
+    mocker.patch('app.main.views.email_branding.upload_email_logo', return_value=temp_filename)
+    mocker.patch('app.main.views.email_branding.delete_email_temp_file')
 
     response = logged_in_platform_admin_client.post(
         url_for('main.create_email_branding'),
@@ -463,12 +463,12 @@ def test_logo_persisted_when_organisation_saved(
     with logged_in_platform_admin_client.session_transaction() as session:
         user_id = session["user_id"]
 
-    temp_filename = LOGO_LOCATION_STRUCTURE.format(
+    temp_filename = EMAIL_LOGO_LOCATION_STRUCTURE.format(
         temp=TEMP_TAG.format(user_id=user_id), unique_id=fake_uuid, filename='test.png')
 
-    mocked_upload_logo = mocker.patch('app.main.views.email_branding.upload_logo')
+    mocked_upload_email_logo = mocker.patch('app.main.views.email_branding.upload_email_logo')
     mocked_persist_logo = mocker.patch('app.main.views.email_branding.persist_logo')
-    mocked_delete_temp_files_by = mocker.patch('app.main.views.email_branding.delete_temp_files_created_by')
+    mocked_delete_email_temp_files_by = mocker.patch('app.main.views.email_branding.delete_email_temp_files_created_by')
 
     resp = logged_in_platform_admin_client.post(
         url_for('.create_email_branding', logo=temp_filename),
@@ -476,10 +476,10 @@ def test_logo_persisted_when_organisation_saved(
     )
     assert resp.status_code == 302
 
-    assert not mocked_upload_logo.called
+    assert not mocked_upload_email_logo.called
     assert mocked_persist_logo.called
-    assert mocked_delete_temp_files_by.called
-    assert mocked_delete_temp_files_by.call_args == call(user_id)
+    assert mocked_delete_email_temp_files_by.called
+    assert mocked_delete_email_temp_files_by.call_args == call(user_id)
     assert mock_create_email_branding.called
 
 
@@ -492,11 +492,11 @@ def test_logo_does_not_get_persisted_if_updating_email_branding_client_throws_an
     with logged_in_platform_admin_client.session_transaction() as session:
         user_id = session["user_id"]
 
-    temp_filename = LOGO_LOCATION_STRUCTURE.format(
+    temp_filename = EMAIL_LOGO_LOCATION_STRUCTURE.format(
         temp=TEMP_TAG.format(user_id=user_id), unique_id=fake_uuid, filename='test.png')
 
     mocked_persist_logo = mocker.patch('app.main.views.email_branding.persist_logo')
-    mocked_delete_temp_files_by = mocker.patch('app.main.views.email_branding.delete_temp_files_created_by')
+    mocked_delete_email_temp_files_by = mocker.patch('app.main.views.email_branding.delete_email_temp_files_created_by')
     mocker.patch('app.main.views.email_branding.email_branding_client.create_email_branding', side_effect=HTTPError())
 
     logged_in_platform_admin_client.post(
@@ -505,7 +505,7 @@ def test_logo_does_not_get_persisted_if_updating_email_branding_client_throws_an
     )
 
     assert not mocked_persist_logo.called
-    assert not mocked_delete_temp_files_by.called
+    assert not mocked_delete_email_temp_files_by.called
 
 
 @pytest.mark.parametrize('colour_hex, expected_status_code', [
@@ -530,7 +530,7 @@ def test_colour_regex_validation(
         'brand_type': 'org'
     }
 
-    mocker.patch('app.main.views.email_branding.delete_temp_files_created_by')
+    mocker.patch('app.main.views.email_branding.delete_email_temp_files_created_by')
 
     response = logged_in_platform_admin_client.post(
         url_for('.create_email_branding'),
diff --git a/tests/app/main/views/test_letter_branding.py b/tests/app/main/views/test_letter_branding.py
new file mode 100644
index 000000000..21eab361e
--- /dev/null
+++ b/tests/app/main/views/test_letter_branding.py
@@ -0,0 +1,274 @@
+from io import BytesIO
+from unittest.mock import Mock
+
+import pytest
+from bs4 import BeautifulSoup
+from flask import current_app, url_for
+from notifications_python_client.errors import HTTPError
+
+from app.main.views.letter_branding import get_png_file_from_svg
+from app.s3_client.s3_logo_client import LETTER_TEMP_LOGO_LOCATION
+
+
+def test_create_letter_branding_does_not_show_branding_info(logged_in_platform_admin_client):
+    response = logged_in_platform_admin_client.get(
+        url_for('.create_letter_branding')
+    )
+
+    assert response.status_code == 200
+    page = BeautifulSoup(response.data.decode('utf-8'), 'html.parser')
+
+    assert page.select_one('#logo-img > img') is None
+    assert page.select_one('#name').attrs.get('value') == ''
+    assert page.select_one('#domain').attrs.get('value') == ''
+
+
+def test_create_letter_branding_when_uploading_valid_file(
+    mocker,
+    logged_in_platform_admin_client,
+    fake_uuid
+):
+    with logged_in_platform_admin_client.session_transaction() as session:
+        user_id = session["user_id"]
+
+    filename = 'test.svg'
+    expected_temp_filename = LETTER_TEMP_LOGO_LOCATION.format(user_id=user_id, unique_id=fake_uuid, filename=filename)
+
+    mock_s3_upload = mocker.patch('app.s3_client.s3_logo_client.utils_s3upload')
+    mocker.patch('app.s3_client.s3_logo_client.uuid.uuid4', return_value=fake_uuid)
+    mock_delete_temp_files = mocker.patch('app.main.views.letter_branding.delete_letter_temp_file')
+
+    response = logged_in_platform_admin_client.post(
+        url_for('.create_letter_branding'),
+        data={'file': (BytesIO(''.encode('utf-8')), filename)},
+        follow_redirects=True
+    )
+
+    assert response.status_code == 200
+    page = BeautifulSoup(response.data.decode('utf-8'), 'html.parser')
+
+    assert page.select_one('#logo-img > img').attrs['src'].endswith(expected_temp_filename)
+    assert mock_s3_upload.called
+    mock_delete_temp_files.assert_not_called()
+
+
+def test_create_letter_branding_when_uploading_invalid_file(logged_in_platform_admin_client):
+    response = logged_in_platform_admin_client.post(
+        url_for('.create_letter_branding'),
+        data={'file': (BytesIO(''.encode('utf-8')), 'test.png')},
+        follow_redirects=True
+    )
+
+    assert response.status_code == 200
+    page = BeautifulSoup(response.data.decode('utf-8'), 'html.parser')
+
+    assert page.find('h1').text == 'Add letter branding'
+    assert page.select_one('.error-message').text.strip() == 'SVG Images only!'
+
+
+def test_create_letter_branding_deletes_temp_files_when_uploading_a_new_file(
+    mocker,
+    logged_in_platform_admin_client,
+    fake_uuid,
+):
+    with logged_in_platform_admin_client.session_transaction() as session:
+        user_id = session["user_id"]
+
+    temp_logo = LETTER_TEMP_LOGO_LOCATION.format(user_id=user_id, unique_id=fake_uuid, filename='temp.svg')
+
+    mock_s3_upload = mocker.patch('app.s3_client.s3_logo_client.utils_s3upload')
+    mock_delete_temp_files = mocker.patch('app.main.views.letter_branding.delete_letter_temp_file')
+
+    response = logged_in_platform_admin_client.post(
+        url_for('.create_letter_branding', logo=temp_logo),
+        data={'file': (BytesIO(''.encode('utf-8')), 'new.svg')},
+        follow_redirects=True
+    )
+
+    assert response.status_code == 200
+    page = BeautifulSoup(response.data.decode('utf-8'), 'html.parser')
+
+    assert mock_s3_upload.called
+    assert mock_delete_temp_files.called
+    assert page.find('h1').text == 'Add letter branding'
+
+
+def test_create_new_letter_branding_shows_preview_of_logo(
+    mocker,
+    logged_in_platform_admin_client,
+    fake_uuid
+):
+    with logged_in_platform_admin_client.session_transaction() as session:
+        user_id = session["user_id"]
+
+    temp_logo = LETTER_TEMP_LOGO_LOCATION.format(user_id=user_id, unique_id=fake_uuid, filename='temp.svg')
+
+    response = logged_in_platform_admin_client.get(
+        url_for('.create_letter_branding', logo=temp_logo)
+    )
+
+    assert response.status_code == 200
+    page = BeautifulSoup(response.data.decode('utf-8'), 'html.parser')
+
+    assert page.find('h1').text == 'Add letter branding'
+    assert page.select_one('#logo-img > img').attrs['src'].endswith(temp_logo)
+
+
+def test_create_letter_branding_shows_an_error_when_submitting_details_with_no_logo(
+    logged_in_platform_admin_client,
+    fake_uuid
+):
+    response = logged_in_platform_admin_client.post(
+        url_for('.create_letter_branding'),
+        data={
+            'name': 'Test brand',
+            'domain': 'bl.uk',
+            'operation': 'branding-details'
+        }
+    )
+
+    assert response.status_code == 200
+    page = BeautifulSoup(response.data.decode('utf-8'), 'html.parser')
+
+    assert page.find('h1').text == 'Add letter branding'
+    assert page.select_one('.error-message').text.strip() == 'You need to upload a file to submit'
+
+
+@pytest.mark.parametrize('domain', ['bl.uk', ''])
+def test_create_letter_branding_persists_logo_when_all_data_is_valid(
+    mocker,
+    logged_in_platform_admin_client,
+    fake_uuid,
+    domain
+):
+    with logged_in_platform_admin_client.session_transaction() as session:
+        user_id = session["user_id"]
+
+    temp_logo = LETTER_TEMP_LOGO_LOCATION.format(user_id=user_id, unique_id=fake_uuid, filename='test.svg')
+
+    mock_letter_client = mocker.patch('app.main.views.letter_branding.letter_branding_client')
+    mock_template_preview = mocker.patch(
+        'app.main.views.letter_branding.get_png_file_from_svg',
+        return_value='fake_png')
+    mock_persist_logo = mocker.patch('app.main.views.letter_branding.persist_logo')
+    mock_upload_png = mocker.patch('app.main.views.letter_branding.upload_letter_png_logo')
+    mock_delete_temp_files = mocker.patch('app.main.views.letter_branding.delete_letter_temp_files_created_by')
+
+    # TODO: remove platform admin page mocks once we no longer redirect there
+    mocker.patch('app.main.views.platform_admin.make_columns')
+    mocker.patch('app.main.views.platform_admin.platform_stats_api_client.get_aggregate_platform_stats')
+    mocker.patch('app.main.views.platform_admin.complaint_api_client.get_complaint_count')
+
+    response = logged_in_platform_admin_client.post(
+        url_for('.create_letter_branding', logo=temp_logo),
+        data={
+            'name': 'Test brand',
+            'domain': 'bl.uk',
+            'operation': 'branding-details'
+        },
+        follow_redirects=True
+    )
+
+    assert response.status_code == 200
+
+    mock_letter_client.create_letter_branding.assert_called_once_with(
+        domain='bl.uk', filename='{}-test'.format(fake_uuid), name='Test brand'
+    )
+    assert mock_template_preview.called
+    mock_persist_logo.assert_called_once_with(
+        temp_logo,
+        'letters/static/images/letter-template/{}-test.svg'.format(fake_uuid)
+    )
+    mock_upload_png.assert_called_once_with(
+        'letters/static/images/letter-template/{}-test.png'.format(fake_uuid),
+        'fake_png',
+        current_app.config['AWS_REGION']
+    )
+    mock_delete_temp_files.assert_called_once_with(user_id)
+
+
+def test_create_letter_branding_shows_form_errors_on_name_and_domain_fields(
+    logged_in_platform_admin_client,
+    fake_uuid
+):
+    with logged_in_platform_admin_client.session_transaction() as session:
+        user_id = session["user_id"]
+
+    temp_logo = LETTER_TEMP_LOGO_LOCATION.format(user_id=user_id, unique_id=fake_uuid, filename='test.svg')
+
+    response = logged_in_platform_admin_client.post(
+        url_for('.create_letter_branding', logo=temp_logo),
+        data={
+            'name': '',
+            'domain': 'example.com',
+            'operation': 'branding-details'
+        }
+    )
+
+    page = BeautifulSoup(response.data.decode('utf-8'), 'html.parser')
+    error_messages = page.find_all('span', class_='error-message')
+
+    assert page.find('h1').text == 'Add letter branding'
+    assert len(error_messages) == 2
+    assert error_messages[0].text.strip() == 'This field is required.'
+    assert error_messages[1].text.strip() == 'Not a known government domain (you might need to update domains.yml)'
+
+
+@pytest.mark.parametrize('error_field', ['name', 'domain'])
+def test_create_letter_branding_shows_database_errors_on_name_and_domain_fields(
+    mocker,
+    logged_in_platform_admin_client,
+    fake_uuid,
+    error_field
+):
+    with logged_in_platform_admin_client.session_transaction() as session:
+        user_id = session["user_id"]
+
+    mocker.patch('app.main.views.letter_branding.get_png_file_from_svg')
+    mocker.patch('app.main.views.letter_branding.letter_branding_client.create_letter_branding', side_effect=HTTPError(
+        response=Mock(
+            status_code=400,
+            json={
+                'result': 'error',
+                'message': {
+                    error_field: {
+                        '{} already in use'.format(error_field)
+                    }
+                }
+            }
+        ),
+        message={error_field: ['{} already in use'.format(error_field)]}
+    ))
+
+    temp_logo = LETTER_TEMP_LOGO_LOCATION.format(user_id=user_id, unique_id=fake_uuid, filename='test.svg')
+
+    response = logged_in_platform_admin_client.post(
+        url_for('.create_letter_branding', logo=temp_logo),
+        data={
+            'name': 'my brand',
+            'domain': None,
+            'operation': 'branding-details'
+        }
+    )
+
+    page = BeautifulSoup(response.data.decode('utf-8'), 'html.parser')
+    error_message = page.find('span', class_='error-message').text.strip()
+
+    assert page.find('h1').text == 'Add letter branding'
+    assert error_message == '{} already in use'.format(error_field)
+
+
+def test_get_png_file_from_svg(client, mocker, fake_uuid):
+    mocker.patch.dict(
+        'flask.current_app.config',
+        {'TEMPLATE_PREVIEW_API_HOST': 'localhost', 'TEMPLATE_PREVIEW_API_KEY': 'abc'}
+    )
+    tp_mock = mocker.patch('app.main.views.letter_branding.requests_get')
+    filename = LETTER_TEMP_LOGO_LOCATION.format(user_id=fake_uuid, unique_id=fake_uuid, filename='test.svg')
+
+    get_png_file_from_svg(filename)
+
+    tp_mock.assert_called_once_with(
+        'localhost/temp-{}_{}-test.svg.png'.format(fake_uuid, fake_uuid),
+        headers={'Authorization': 'Token abc'}
+    )
diff --git a/tests/app/notify_client/test_letter_branding_client.py b/tests/app/notify_client/test_letter_branding_client.py
index eceadf474..23f962971 100644
--- a/tests/app/notify_client/test_letter_branding_client.py
+++ b/tests/app/notify_client/test_letter_branding_client.py
@@ -7,3 +7,17 @@ def test_get_letter_branding(mocker):
     mock_get.assert_called_once_with(
         url='/dvla_organisations'
     )
+
+
+def test_create_letter_branding(mocker):
+    new_branding = {'filename': 'uuid-test', 'name': 'my letters', 'domain': 'example.com'}
+
+    mock_post = mocker.patch('app.notify_client.letter_branding_client.LetterBrandingClient.post')
+
+    LetterBrandingClient().create_letter_branding(
+        filename=new_branding['filename'], name=new_branding['name'], domain=new_branding['domain']
+    )
+    mock_post.assert_called_once_with(
+        url='/letter-branding',
+        data=new_branding
+    )
diff --git a/tests/app/s3_client/__init__.py b/tests/app/s3_client/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/app/s3_client/test_s3_csv_client.py b/tests/app/s3_client/test_s3_csv_client.py
new file mode 100644
index 000000000..f4014065f
--- /dev/null
+++ b/tests/app/s3_client/test_s3_csv_client.py
@@ -0,0 +1,21 @@
+from unittest.mock import Mock
+
+from app.s3_client.s3_csv_client import set_metadata_on_csv_upload
+
+
+def test_sets_metadata(client, mocker):
+    mocked_s3_object = Mock()
+    mocked_get_s3_object = mocker.patch(
+        'app.s3_client.s3_csv_client.get_csv_upload',
+        return_value=mocked_s3_object,
+    )
+
+    set_metadata_on_csv_upload('1234', '5678', foo='bar', baz=True)
+
+    mocked_get_s3_object.assert_called_once_with('1234', '5678')
+    mocked_s3_object.copy_from.assert_called_once_with(
+        CopySource='test-notifications-csv-upload/service-1234-notify/5678.csv',
+        Metadata={'baz': 'True', 'foo': 'bar'},
+        MetadataDirective='REPLACE',
+        ServerSideEncryption='AES256',
+    )
diff --git a/tests/app/s3_client/test_s3_logo_client.py b/tests/app/s3_client/test_s3_logo_client.py
new file mode 100644
index 000000000..29cedd4a9
--- /dev/null
+++ b/tests/app/s3_client/test_s3_logo_client.py
@@ -0,0 +1,203 @@
+from collections import namedtuple
+from unittest.mock import call
+
+import pytest
+
+from app.s3_client.s3_logo_client import (
+    EMAIL_LOGO_LOCATION_STRUCTURE,
+    LETTER_TEMP_LOGO_LOCATION,
+    LETTER_TEMP_TAG,
+    TEMP_TAG,
+    delete_email_temp_file,
+    delete_email_temp_files_created_by,
+    delete_letter_temp_file,
+    delete_letter_temp_files_created_by,
+    letter_filename_for_db,
+    permanent_email_logo_name,
+    persist_logo,
+    upload_email_logo,
+    upload_letter_png_logo,
+    upload_letter_temp_logo,
+)
+
+bucket = 'test_bucket'
+data = {'data': 'some_data'}
+filename = 'test.png'
+svg_filename = 'test.svg'
+upload_id = 'test_uuid'
+region = 'eu-west1'
+
+
+@pytest.fixture
+def upload_filename(fake_uuid):
+    return EMAIL_LOGO_LOCATION_STRUCTURE.format(
+        temp=TEMP_TAG.format(user_id=fake_uuid), unique_id=upload_id, filename=filename)
+
+
+@pytest.fixture
+def letter_upload_filename(fake_uuid):
+    return LETTER_TEMP_LOGO_LOCATION.format(
+        user_id=fake_uuid,
+        unique_id=upload_id,
+        filename=svg_filename
+    )
+
+
+def test_upload_email_logo_calls_correct_args(client, mocker, fake_uuid, upload_filename):
+    mocker.patch('uuid.uuid4', return_value=upload_id)
+    mocker.patch.dict('flask.current_app.config', {'LOGO_UPLOAD_BUCKET_NAME': bucket})
+    mocked_s3_upload = mocker.patch('app.s3_client.s3_logo_client.utils_s3upload')
+
+    upload_email_logo(filename=filename, user_id=fake_uuid, filedata=data, region=region)
+
+    mocked_s3_upload.assert_called_once_with(
+        filedata=data,
+        region=region,
+        file_location=upload_filename,
+        bucket_name=bucket,
+        content_type='image/png'
+    )
+
+
+def test_upload_letter_temp_logo_calls_correct_args(mocker, fake_uuid, letter_upload_filename):
+    mocker.patch('uuid.uuid4', return_value=upload_id)
+    mocker.patch.dict('flask.current_app.config', {'LOGO_UPLOAD_BUCKET_NAME': bucket})
+    mocked_s3_upload = mocker.patch('app.s3_client.s3_logo_client.utils_s3upload')
+
+    new_filename = upload_letter_temp_logo(filename=svg_filename, user_id=fake_uuid, filedata=data, region=region)
+
+    mocked_s3_upload.assert_called_once_with(
+        filedata=data,
+        region=region,
+        bucket_name=bucket,
+        file_location=letter_upload_filename,
+        content_type='image/svg+xml'
+    )
+    assert new_filename == 'letters/static/images/letter-template/temp-{}_test_uuid-test.svg'.format(fake_uuid)
+
+
+def test_upload_letter_png_logo_calls_correct_args(mocker):
+    mocked_s3_upload = mocker.patch('app.s3_client.s3_logo_client.utils_s3upload')
+    mocker.patch.dict('flask.current_app.config', {'LOGO_UPLOAD_BUCKET_NAME': bucket})
+
+    upload_letter_png_logo(filename, data, region)
+
+    mocked_s3_upload.assert_called_once_with(
+        filedata=data,
+        region=region,
+        bucket_name=bucket,
+        file_location=filename,
+        content_type='image/png'
+    )
+
+
+def test_persist_logo(client, mocker, fake_uuid, upload_filename):
+    mocker.patch.dict('flask.current_app.config', {'LOGO_UPLOAD_BUCKET_NAME': bucket})
+    mocked_get_s3_object = mocker.patch('app.s3_client.s3_logo_client.get_s3_object')
+    mocked_delete_s3_object = mocker.patch('app.s3_client.s3_logo_client.delete_s3_object')
+
+    new_filename = permanent_email_logo_name(upload_filename, fake_uuid)
+
+    persist_logo(upload_filename, new_filename)
+
+    mocked_get_s3_object.assert_called_once_with(bucket, new_filename)
+    mocked_delete_s3_object.assert_called_once_with(upload_filename)
+
+
+def test_persist_logo_returns_if_not_temp(client, mocker, fake_uuid):
+    filename = 'logo.png'
+    persist_logo(filename, filename)
+
+    mocked_get_s3_object = mocker.patch('app.s3_client.s3_logo_client.get_s3_object')
+    mocked_delete_s3_object = mocker.patch('app.s3_client.s3_logo_client.delete_s3_object')
+
+    mocked_get_s3_object.assert_not_called()
+    mocked_delete_s3_object.assert_not_called()
+
+
+def test_permanent_email_logo_name_removes_TEMP_TAG_from_filename(upload_filename, fake_uuid):
+    new_name = permanent_email_logo_name(upload_filename, fake_uuid)
+
+    assert new_name == 'test_uuid-test.png'
+
+
+def test_permanent_email_logo_name_does_not_change_filenames_with_no_TEMP_TAG():
+    filename = 'logo.png'
+    new_name = permanent_email_logo_name(filename, filename)
+
+    assert new_name == filename
+
+
+def test_letter_filename_for_db_when_file_has_a_temp_tag(fake_uuid):
+    temp_filename = LETTER_TEMP_LOGO_LOCATION.format(user_id=fake_uuid, unique_id=upload_id, filename=svg_filename)
+    assert letter_filename_for_db(temp_filename, fake_uuid) == 'test_uuid-test'
+
+
+def test_letter_filename_for_db_when_file_does_not_have_a_temp_tag(fake_uuid):
+    filename = 'letters/static/images/letter-template/{}-test.svg'.format(fake_uuid)
+    assert letter_filename_for_db(filename, fake_uuid) == '{}-test'.format(fake_uuid)
+
+
+def test_delete_email_temp_files_created_by_user(client, mocker, fake_uuid):
+    obj = namedtuple("obj", ["key"])
+    objs = [obj(key='test1'), obj(key='test2')]
+
+    mocker.patch('app.s3_client.s3_logo_client.get_s3_objects_filter_by_prefix', return_value=objs)
+    mocked_delete_s3_object = mocker.patch('app.s3_client.s3_logo_client.delete_s3_object')
+
+    delete_email_temp_files_created_by(fake_uuid)
+
+    for index, arg in enumerate(mocked_delete_s3_object.call_args_list):
+        assert arg == call(objs[index].key)
+
+
+def test_delete_letter_temp_files_created_by_user(mocker, fake_uuid):
+    obj = namedtuple("obj", ["key"])
+    objs = [obj(key='test1'), obj(key='test2')]
+
+    mocker.patch('app.s3_client.s3_logo_client.get_s3_objects_filter_by_prefix', return_value=objs)
+    mocked_delete_s3_object = mocker.patch('app.s3_client.s3_logo_client.delete_s3_object')
+
+    delete_letter_temp_files_created_by(fake_uuid)
+
+    for index, arg in enumerate(mocked_delete_s3_object.call_args_list):
+        assert arg == call(objs[index].key)
+
+
+def test_delete_single_email_temp_file(client, mocker, upload_filename):
+    mocked_delete_s3_object = mocker.patch('app.s3_client.s3_logo_client.delete_s3_object')
+
+    delete_email_temp_file(upload_filename)
+
+    mocked_delete_s3_object.assert_called_with(upload_filename)
+
+
+def test_does_not_delete_non_temp_email_file(client, mocker):
+    filename = 'logo.png'
+    mocked_delete_s3_object = mocker.patch('app.s3_client.s3_logo_client.delete_s3_object')
+
+    with pytest.raises(ValueError) as error:
+        delete_email_temp_file(filename)
+
+    mocked_delete_s3_object.assert_not_called
+    assert str(error.value) == 'Not a temp file: {}'.format(filename)
+
+
+def test_delete_single_temp_letter_file(mocker, fake_uuid, upload_filename):
+    mocked_delete_s3_object = mocker.patch('app.s3_client.s3_logo_client.delete_s3_object')
+
+    upload_filename = LETTER_TEMP_TAG.format(user_id=fake_uuid) + svg_filename
+
+    delete_letter_temp_file(upload_filename)
+
+    mocked_delete_s3_object.assert_called_with(upload_filename)
+
+
+def test_does_not_delete_non_temp_letter_file(mocker, fake_uuid):
+    mocked_delete_s3_object = mocker.patch('app.s3_client.s3_logo_client.delete_s3_object')
+
+    with pytest.raises(ValueError) as error:
+        delete_letter_temp_file(svg_filename)
+
+    mocked_delete_s3_object.assert_not_called
+    assert str(error.value) == 'Not a temp file: {}'.format(svg_filename)
diff --git a/tests/app/test_utils.py b/tests/app/test_utils.py
index d65cafbb5..7bdfd4ebf 100644
--- a/tests/app/test_utils.py
+++ b/tests/app/test_utils.py
@@ -210,7 +210,7 @@ def test_generate_notifications_csv_returns_correct_csv_file(
     expected_1st_row,
 ):
     mocker.patch(
-        'app.main.s3_client.s3download',
+        'app.s3_client.s3_csv_client.s3download',
         return_value=original_file_contents,
     )
     csv_content = generate_notifications_csv(service_id='1234', job_id=fake_uuid, template_type='sms')
@@ -236,7 +236,7 @@ def test_generate_notifications_csv_calls_twice_if_next_link(
 ):
 
     mocker.patch(
-        'app.main.s3_client.s3download',
+        'app.s3_client.s3_csv_client.s3download',
         return_value="""
             phone_number
             07700900000