diff --git a/README.md b/README.md
index 0d8eab4570..a9291ba609 100644
--- a/README.md
+++ b/README.md
@@ -1,23 +1,23 @@
 # GOV.UK Prototype Kit
 
-Go to the [GOV.UK Prototype Kit site](https://govuk-prototype-kit.herokuapp.com/docs) to download the latest version and read the documentation.
+Go to the [GOV.UK Prototype Kit site](https://prototype-kit.service.gov.uk/docs) to download the latest version and read the documentation.
 
 ## About the Prototype Kit
 
 The Prototype Kit provides a simple way to make interactive prototypes that look like pages on GOV.UK. These prototypes can be used to show ideas to people you work with, and to do user research.
 
-Read the [project principles](https://govuk-prototype-kit.herokuapp.com/docs/principles).
+Read the [project principles](https://prototype-kit.service.gov.uk/docs/principles).
 
 ## Make sure prototypes are password-protected
 
-If you publish your prototypes online, they **must** be protected by a [username and password](https://govuk-prototype-kit.herokuapp.com/docs/publishing-on-heroku). This is to prevent members of the public finding prototypes and thinking they are real services.
+If you publish your prototypes online, they **must** be [protected by a password](https://prototype-kit.service.gov.uk/docs/publishing). This is to prevent members of the public finding prototypes and thinking they are real services.
 
 You must protect user privacy at all times, even when using prototypes. Prototypes made with the kit look like GOV.UK, but do not have the same security provisions. Always make sure you are handling user data appropriately.
 
 ## Installation instructions
 
-- [Installation guide for new users (non technical)](https://govuk-prototype-kit.herokuapp.com/docs/install/introduction)
-- [Installation guide for developers (technical)](https://govuk-prototype-kit.herokuapp.com/docs/install/developer-install-instructions)
+- [Installation guide for new users (non technical)](https://prototype-kit.service.gov.uk/docs/install/introduction)
+- [Installation guide for developers (technical)](https://prototype-kit.service.gov.uk/docs/install/developer-install-instructions)
 
 ## Node version requirements
 
diff --git a/internal_docs/releasing-from-a-support-branch.md b/internal_docs/releasing-from-a-support-branch.md
index f1653c2198..4f734e88e2 100644
--- a/internal_docs/releasing-from-a-support-branch.md
+++ b/internal_docs/releasing-from-a-support-branch.md
@@ -96,7 +96,7 @@ Write a brief summary with highlights from the release then send it to the follo
 - X-GOV #prototype-kit
 - GDS #govuk-design-system
 
-Include a link to the install page: https://govuk-prototype-kit.herokuapp.com/docs/install.
+Include a link to the install page: https://prototype-kit.service.gov.uk/docs/install.
 
 Include a link to the GitHub release page if there are actions for users that are not covered in the release notes.
 
diff --git a/internal_docs/releasing.md b/internal_docs/releasing.md
index 85eafef6bb..5ad0daeb6a 100644
--- a/internal_docs/releasing.md
+++ b/internal_docs/releasing.md
@@ -66,4 +66,4 @@ Write a brief summary with highlights from the release then send it to the follo
 - X-GOV #prototype-kit
 - GDS #govuk-design-system
 
-Make sure to send a link to the install page rather than the GitHub release page: https://govuk-prototype-kit.herokuapp.com/docs/install.
+Make sure to send a link to the install page rather than the GitHub release page: https://prototype-kit.service.gov.uk/docs/install.
diff --git a/lib/assets/sass/unbranded.scss b/lib/assets/sass/unbranded.scss
index 09966091cd..8f935ccdb0 100644
--- a/lib/assets/sass/unbranded.scss
+++ b/lib/assets/sass/unbranded.scss
@@ -1,7 +1,7 @@
 // The unbranded stylesheet is used if you need to create pages in your
 // prototype without the GOV.UK branding.
 //
-// See https://govuk-prototype-kit.herokuapp.com/docs/templates/blank-unbranded
+// See https://prototype-kit.service.gov.uk/docs/templates/blank-unbranded
 
 // Override the default GOV.UK Frontend font stack
 $govuk-font-family: "HelveticaNeue", "Helvetica Neue", "Arial", "Helvetica", sans-serif;
diff --git a/lib/middleware/authentication/authentication.js b/lib/middleware/authentication/authentication.js
index 965168b691..88fe32b855 100644
--- a/lib/middleware/authentication/authentication.js
+++ b/lib/middleware/authentication/authentication.js
@@ -59,7 +59,7 @@ function shouldUseAuth () {
 
 function showNoPasswordError (res) {
   console.error('Password is not set.')
-  return res.send('<h1>Error:</h1><p>Password not set. <a href="https://govuk-prototype-kit.herokuapp.com/docs/publishing-on-heroku#6-set-a-password">See guidance for setting a password</a>.</p>')
+  return res.send('<h1>Error:</h1><p>Password not set. <a href="https://prototype-kit.service.gov.uk/docs/publishing#setting-a-password">See guidance for setting a password</a>.</p>')
 }
 
 function sendUserToPasswordPage (req, res) {
diff --git a/lib/middleware/authentication/authentication.test.js b/lib/middleware/authentication/authentication.test.js
index e34849253f..8e7f3bb467 100644
--- a/lib/middleware/authentication/authentication.test.js
+++ b/lib/middleware/authentication/authentication.test.js
@@ -77,7 +77,7 @@ describe('authentication', () => {
 
       it('should return a user friendly error to the browser', () => {
         const errorDisplayedToUser = res.send.mock.calls[0][0]
-        expect(errorDisplayedToUser).toBe('<h1>Error:</h1><p>Password not set. <a href="https://govuk-prototype-kit.herokuapp.com/docs/publishing-on-heroku#6-set-a-password">See guidance for setting a password</a>.</p>')
+        expect(errorDisplayedToUser).toBe('<h1>Error:</h1><p>Password not set. <a href="https://prototype-kit.service.gov.uk/docs/publishing#setting-a-password">See guidance for setting a password</a>.</p>')
       })
     })
 
diff --git a/lib/migrator/index.js b/lib/migrator/index.js
index 59931eecc5..300a3e7952 100644
--- a/lib/migrator/index.js
+++ b/lib/migrator/index.js
@@ -1,6 +1,6 @@
 const logger = require('./logger')
 
-const supportPage = 'https://govuk-prototype-kit.herokuapp.com/docs/support'
+const supportPage = 'https://prototype-kit.service.gov.uk/docs/support'
 
 const {
   preflightChecks,
diff --git a/lib/nunjucks/govuk-prototype-kit/internal/views/manage-prototype/index.njk b/lib/nunjucks/govuk-prototype-kit/internal/views/manage-prototype/index.njk
index 0b3cf9191a..43f5796e0b 100644
--- a/lib/nunjucks/govuk-prototype-kit/internal/views/manage-prototype/index.njk
+++ b/lib/nunjucks/govuk-prototype-kit/internal/views/manage-prototype/index.njk
@@ -19,7 +19,7 @@
           </p>
         {% endif %}
         <p>
-          <a href="https://govuk-prototype-kit.herokuapp.com/">Prototype Kit website</a>
+          <a href="https://prototype-kit.service.gov.uk/">Prototype Kit website</a>
           for guidance and tutorials
         </p>
       </div>
diff --git a/lib/usage-data-prompt.txt b/lib/usage-data-prompt.txt
index e3e6b92374..f3ddd0eddc 100644
--- a/lib/usage-data-prompt.txt
+++ b/lib/usage-data-prompt.txt
@@ -4,6 +4,6 @@ Help us improve the GOV.UK Prototype Kit
 
 With your permission, the kit can send useful anonymous usage data
 for analysis to help the team improve the service. Read more here:
-https://govuk-prototype-kit.herokuapp.com/docs/usage-data
+https://prototype-kit.service.gov.uk/docs/usage-data
 
 Do you give permission for the kit to send anonymous usage data?
diff --git a/server.js b/server.js
index bd0e52be03..a5bcbda12c 100644
--- a/server.js
+++ b/server.js
@@ -160,7 +160,7 @@ app.post(/^\/([^.]+)$/, function (req, res) {
 
 // redirect old local docs to the docs site
 app.get('/docs/tutorials-and-examples', function (req, res) {
-  res.redirect('https://govuk-prototype-kit.herokuapp.com/docs')
+  res.redirect('https://prototype-kit.service.gov.uk/docs')
 })
 
 app.get('/', async (req, res) => {