diff --git a/app/main/forms.py b/app/main/forms.py
index b66950051..b16f46a42 100644
--- a/app/main/forms.py
+++ b/app/main/forms.py
@@ -658,6 +658,16 @@ class ServiceInboundApiForm(Form):
                                                            Length(min=10, message='Must be at least 10 characters')])
 
 
+class InternationalSMSForm(Form):
+    enabled = RadioField(
+        'Send text messages to international phone numbers',
+        choices=[
+            ('on', 'On'),
+            ('off', 'Off'),
+        ],
+    )
+
+
 def get_placeholder_form_instance(
     placeholder_name,
     dict_to_populate_from,
diff --git a/app/main/views/service_settings.py b/app/main/views/service_settings.py
index 866d19873..2f1d1472f 100644
--- a/app/main/views/service_settings.py
+++ b/app/main/views/service_settings.py
@@ -32,7 +32,9 @@ from app.main.forms import (
     ServiceLetterContactBlock,
     ServiceBrandingOrg,
     LetterBranding,
-    ServiceInboundApiForm)
+    ServiceInboundApiForm,
+    InternationalSMSForm,
+)
 from app import user_api_client, current_service, organisations_client, inbound_number_client
 
 
@@ -222,13 +224,22 @@ def service_switch_research_mode(service_id):
     return redirect(url_for('.service_settings', service_id=service_id))
 
 
-def switch_service_permissions(service_id, permission, sms_sender=None):
+def switch_service_permissions(service_id, permission, sms_sender=None, force=None):
+
     permissions = current_service['permissions'].copy()
-    if permission in permissions:
-        permissions.remove(permission)
+
+    if force is None:
+        if permission in permissions:
+            permissions.remove(permission)
+        else:
+            permissions.append(permission)
     else:
-        permissions.append(permission)
-    current_service['permissions'] = permissions
+        if force is True:
+            permissions.append(permission)
+        elif force is False and permission in permissions:
+            permissions.remove(permission)
+
+    current_service['permissions'] = list(set(permissions))
 
     data = {'permissions': permissions}
     if sms_sender:
@@ -423,12 +434,25 @@ def service_set_sms(service_id):
     )
 
 
-@main.route("/services/<service_id>/service-settings/set-international-sms", methods=['GET'])
+@main.route("/services/<service_id>/service-settings/set-international-sms", methods=['GET', 'POST'])
 @login_required
 @user_has_permissions('manage_settings', admin_override=True)
 def service_set_international_sms(service_id):
+    form = InternationalSMSForm(
+        enabled='on' if 'international_sms' in current_service['permissions'] else 'off'
+    )
+    if form.validate_on_submit():
+        switch_service_permissions(
+            service_id,
+            'international_sms',
+            force=False if form.enabled.data == 'off' else True,
+        )
+        return redirect(
+            url_for(".service_settings", service_id=service_id)
+        )
     return render_template(
         'views/service-settings/set-international-sms.html',
+        form=form,
     )
 
 
diff --git a/app/templates/views/service-settings.html b/app/templates/views/service-settings.html
index 193705cf1..ebce22710 100644
--- a/app/templates/views/service-settings.html
+++ b/app/templates/views/service-settings.html
@@ -231,11 +231,6 @@
           </a>
         </li>
         {% if 'sms' in current_service.permissions %}
-          <li class="bottom-gutter">
-            <a href="{{ url_for('.service_switch_can_send_international_sms', service_id=current_service.id) }}" class="button">
-              {{ 'Stop sending international sms' if 'international_sms' in current_service.permissions else 'Allow to send international sms' }}
-            </a>
-          </li>
           <li class="bottom-gutter">
           {% if can_receive_inbound %}
             <a href="{{ url_for('.service_set_inbound_number', service_id=current_service.id, set_inbound_sms=False) }}" class="button">
diff --git a/app/templates/views/service-settings/set-international-sms.html b/app/templates/views/service-settings/set-international-sms.html
index 6b0c683eb..13568c94a 100644
--- a/app/templates/views/service-settings/set-international-sms.html
+++ b/app/templates/views/service-settings/set-international-sms.html
@@ -1,5 +1,5 @@
 {% extends "withnav_template.html" %}
-{% from "components/textbox.html" import textbox %}
+{% from "components/radios.html" import radios %}
 {% from "components/page-footer.html" import page_footer %}
 
 {% block service_page_title %}
@@ -11,28 +11,21 @@
   <div class="grid-row">
     <div class="column-five-sixths">
       <h1 class="heading-large">International text messages</h1>
-      {% if 'international_sms' in current_service.permissions %}
-        <p>
-          Your service can send text messages to international phone numbers.
-        </p>
-        <p>
-          If you want to turn it off,
-          <a href="{{ url_for('.support') }}">get in touch with the GOV.UK Notify team</a>.
-        </p>
-      {% else %}
-        <p>
-          Sending text messages to international phone numbers is an
-          invitation&#8209;only feature.
-        </p>
-        <p>
-          If you want to try it out,
-          <a href="{{ url_for('.support') }}">get in touch with the GOV.UK Notify team</a>.
-        </p>
-      {% endif %}
-      {{ page_footer(
-        back_link=url_for('.service_settings', service_id=current_service.id),
-        back_link_text='Back to settings'
-      ) }}
+      <p>
+        Messages to international mobile numbers are charged at 1, 2, or
+        3 times the cost of messages to UK mobile numbers.</p>
+      <p>
+        See <a href="{{ url_for(".pricing") }}">pricing</a> for the list
+        of rates.
+      </p>
+      <form method="post">
+        {{ radios(form.enabled) }}
+        {{ page_footer(
+          button_text="Save",
+          back_link=url_for('.service_settings', service_id=current_service.id),
+          back_link_text='Back to settings'
+        ) }}
+      </form>
     </div>
   </div>
 
diff --git a/tests/app/main/views/test_service_settings.py b/tests/app/main/views/test_service_settings.py
index ec0eacef4..e720f01c6 100644
--- a/tests/app/main/views/test_service_settings.py
+++ b/tests/app/main/views/test_service_settings.py
@@ -1176,40 +1176,59 @@ def test_switch_service_disable_letters(
     assert mocked_fn.call_args == call(service_one['id'], {"permissions": []})
 
 
+@pytest.mark.parametrize('permissions, expected_checked', [
+    (['international_sms'], 'on'),
+    ([''], 'off'),
+])
+def test_show_international_sms_as_radio_button(
+    client_request,
+    service_one,
+    mocker,
+    permissions,
+    expected_checked,
+):
+    service_one['permissions'] = permissions
+
+    checked_radios = client_request.get(
+        'main.service_set_international_sms',
+        service_id=service_one['id'],
+    ).select(
+        '.multiple-choice input[checked]'
+    )
+
+    assert len(checked_radios) == 1
+    assert checked_radios[0]['value'] == expected_checked
+
+
+@pytest.mark.parametrize('post_value, international_sms_permission_expected_in_api_call', [
+    ('on', True),
+    ('off', False),
+])
 def test_switch_service_enable_international_sms(
-        logged_in_platform_admin_client,
-        service_one,
-        mocker,
+    client_request,
+    service_one,
+    mocker,
+    post_value,
+    international_sms_permission_expected_in_api_call,
 ):
     mocked_fn = mocker.patch('app.service_api_client.update_service_with_properties', return_value=service_one)
-
-    response = logged_in_platform_admin_client.get(
-        url_for('main.service_switch_can_send_international_sms', service_id=service_one['id'])
+    page = client_request.post(
+        'main.service_set_international_sms',
+        service_id=service_one['id'],
+        _data={
+            'enabled': post_value
+        },
+        _expected_redirect=url_for('main.service_settings', service_id=service_one['id'], _external=True)
     )
 
-    assert response.status_code == 302
-    assert response.location == url_for('main.service_settings', service_id=service_one['id'], _external=True)
-    assert 'international_sms' in mocked_fn.call_args[0][1]['permissions']
+    if international_sms_permission_expected_in_api_call:
+        assert 'international_sms' in mocked_fn.call_args[0][1]['permissions']
+    else:
+        assert 'international_sms' not in mocked_fn.call_args[0][1]['permissions']
+
     assert mocked_fn.call_args[0][0] == service_one['id']
 
 
-def test_switch_service_disable_international_sms(
-        logged_in_platform_admin_client,
-        service_one,
-        mocker,
-):
-    service_one['permissions'] = ['international_sms']
-    mocked_fn = mocker.patch('app.service_api_client.update_service_with_properties', return_value=service_one)
-
-    response = logged_in_platform_admin_client.get(
-        url_for('main.service_switch_can_send_international_sms', service_id=service_one['id'])
-    )
-
-    assert response.status_code == 302
-    assert response.location == url_for('main.service_settings', service_id=service_one['id'], _external=True)
-    assert mocked_fn.call_args == call(service_one['id'], {"permissions": []})
-
-
 def test_set_new_inbound_api_and_valid_bearer_token_calls_create_inbound_api_endpoint(
         logged_in_platform_admin_client,
         service_one,
@@ -1466,21 +1485,6 @@ def test_cant_resume_active_service(
 
 
 @pytest.mark.parametrize('endpoint, permissions, expected_p', [
-    (
-        'main.service_set_international_sms',
-        ['sms'],
-        (
-            'Sending text messages to international phone numbers is '
-            'an invitation‑only feature.'
-        )
-    ),
-    (
-        'main.service_set_international_sms',
-        ['sms', 'international_sms'],
-        (
-            'Your service can send text messages to international phone numbers.'
-        )
-    ),
     (
         'main.service_set_letters',
         [],