diff --git a/Makefile b/Makefile
index 6884c678b..58bfd9b3c 100644
--- a/Makefile
+++ b/Makefile
@@ -64,6 +64,7 @@ generate-version-file: ## Generates the app version file
 
 .PHONY: build
 build: dependencies generate-version-file ## Build project
+	./venv/bin/pip-accel wheel --wheel-dir=wheelhouse -r requirements.txt
 
 .PHONY: build-codedeploy-artifact
 build-codedeploy-artifact: ## Build the deploy artifact for CodeDeploy
diff --git a/app/models.py b/app/models.py
index 05b86d4a2..526288990 100644
--- a/app/models.py
+++ b/app/models.py
@@ -123,6 +123,7 @@ class Service(db.Model, Versioned):
         backref=db.backref('user_to_service', lazy='dynamic'))
     restricted = db.Column(db.Boolean, index=False, unique=False, nullable=False)
     research_mode = db.Column(db.Boolean, index=False, unique=False, nullable=False, default=False)
+    can_send_letters = db.Column(db.Boolean, nullable=False, default=False)
     email_from = db.Column(db.Text, index=False, unique=True, nullable=False)
     created_by = db.relationship('User')
     created_by_id = db.Column(UUID(as_uuid=True), db.ForeignKey('users.id'), index=True, nullable=False)
diff --git a/docker/Dockerfile-build b/docker/Dockerfile-build
index 4fa6afb2d..25b071293 100644
--- a/docker/Dockerfile-build
+++ b/docker/Dockerfile-build
@@ -20,6 +20,7 @@ RUN \
 	echo "Install global pip packages" \
 	&& pip install \
 		virtualenv \
-		awscli
+		awscli \
+		wheel
 
 WORKDIR /var/project
diff --git a/migrations/versions/0058_add_letters_flag.py b/migrations/versions/0058_add_letters_flag.py
new file mode 100644
index 000000000..3e7e5fcac
--- /dev/null
+++ b/migrations/versions/0058_add_letters_flag.py
@@ -0,0 +1,24 @@
+"""empty message
+
+Revision ID: 0058_add_letters_flag
+Revises: 0057_change_email_template
+Create Date: 2016-10-25 17:37:27.660723
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '0058_add_letters_flag'
+down_revision = '0057_change_email_template'
+
+from alembic import op
+import sqlalchemy as sa
+
+
+def upgrade():
+    op.add_column('services', sa.Column('can_send_letters', sa.Boolean(), nullable=False, server_default=sa.false()))
+    op.add_column('services_history', sa.Column('can_send_letters', sa.Boolean(), nullable=False, server_default=sa.false()))
+
+
+def downgrade():
+    op.drop_column('services_history', 'can_send_letters')
+    op.drop_column('services', 'can_send_letters')
diff --git a/requirements.txt b/requirements.txt
index 3ffdfb572..dba7c2cfc 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -20,6 +20,6 @@ statsd==3.2.1
 
 git+https://github.com/alphagov/notifications-python-client.git@1.3.0#egg=notifications-python-client==1.3.0
 
-git+https://github.com/alphagov/notifications-utils.git@9.0.5#egg=notifications-utils==9.0.5
+git+https://github.com/alphagov/notifications-utils.git@9.1.1#egg=notifications-utils==9.1.1
 
 git+https://github.com/alphagov/boto.git@2.42.0-patch2#egg=boto==2.42.0-patch2
diff --git a/scripts/aws_install_dependencies.sh b/scripts/aws_install_dependencies.sh
index b82881d45..03daadb21 100755
--- a/scripts/aws_install_dependencies.sh
+++ b/scripts/aws_install_dependencies.sh
@@ -5,4 +5,4 @@ set -eo pipefail
 echo "Install dependencies"
 
 cd /home/notify-app/notifications-api;
-pip3 install -r /home/notify-app/notifications-api/requirements.txt
+pip3 install --find-links=wheelhouse -r /home/notify-app/notifications-api/requirements.txt
diff --git a/tests/app/service/test_rest.py b/tests/app/service/test_rest.py
index 69e382c4e..3959e401d 100644
--- a/tests/app/service/test_rest.py
+++ b/tests/app/service/test_rest.py
@@ -193,6 +193,7 @@ def test_create_service(notify_api, sample_user):
             json_resp = json.loads(resp.get_data(as_text=True))
             assert json_resp['data']['name'] == 'created service'
             assert not json_resp['data']['research_mode']
+            assert not json_resp['data']['can_send_letters']
 
 
 def test_should_not_create_service_with_missing_user_id_field(notify_api, fake_uuid):
@@ -376,7 +377,7 @@ def test_update_service(notify_api, notify_db, sample_service):
             assert result['data']['organisation'] == str(org.id)
 
 
-def test_update_service_research_mode(notify_api, sample_service):
+def test_update_service_flags(notify_api, sample_service):
     with notify_api.test_request_context():
         with notify_api.test_client() as client:
             auth_header = create_authorization_header()
@@ -387,10 +388,12 @@ def test_update_service_research_mode(notify_api, sample_service):
             json_resp = json.loads(resp.get_data(as_text=True))
             assert resp.status_code == 200
             assert json_resp['data']['name'] == sample_service.name
-            assert not json_resp['data']['research_mode']
+            assert json_resp['data']['research_mode'] is False
+            assert json_resp['data']['can_send_letters'] is False
 
             data = {
-                'research_mode': True
+                'research_mode': True,
+                'can_send_letters': True
             }
 
             auth_header = create_authorization_header()
@@ -402,7 +405,8 @@ def test_update_service_research_mode(notify_api, sample_service):
             )
             result = json.loads(resp.get_data(as_text=True))
             assert resp.status_code == 200
-            assert result['data']['research_mode']
+            assert result['data']['research_mode'] is True
+            assert result['data']['can_send_letters'] is True
 
 
 def test_update_service_research_mode_throws_validation_error(notify_api, sample_service):