diff --git a/app/templates/views/features/letters.html b/app/templates/views/features/letters.html
index e7b31508f..433b40882 100644
--- a/app/templates/views/features/letters.html
+++ b/app/templates/views/features/letters.html
@@ -29,7 +29,7 @@
 
   <h3 class="heading heading-small">Upload your own letters</h3>
   <p>You can create reusable letter templates in Notify, or upload and send your own letters with the Notify API.</p>
-  <p>Use the <a href="https://docs.notifications.service.gov.uk/documentation/images/notify-pdf-letter-spec-v2.3.pdf">letter specification document</a> to help you set up your letter, save it as a PDF, then upload it to Notify.<p>
+  <p>Use the <a href="https://docs.notifications.service.gov.uk/documentation/images/notify-pdf-letter-spec-v2.4.pdf">letter specification document</a> to help you set up your letter, save it as a PDF, then upload it to Notify.<p>
   <p>Read our <a href="{{ url_for('.documentation') }}">API documentation</a> for more information.</p>
 
   <h2 class="heading heading-medium">Pricing</h2>
diff --git a/app/templates/views/letter-validation-preview.html b/app/templates/views/letter-validation-preview.html
index f12c1e6be..04674640b 100644
--- a/app/templates/views/letter-validation-preview.html
+++ b/app/templates/views/letter-validation-preview.html
@@ -37,7 +37,7 @@
         </p>
         <p>The content of your letter must appear inside the printable area.</p>
         <p>
-        <a href="https://docs.notifications.service.gov.uk/documentation/images/notify-pdf-letter-spec-v2.3.pdf">
+        <a href="https://docs.notifications.service.gov.uk/documentation/images/notify-pdf-letter-spec-v2.4.pdf">
             Download the letter specification</a> for more information.
         </p>
         </div>
diff --git a/app/templates/views/uploads/choose-file.html b/app/templates/views/uploads/choose-file.html
index 435081ac9..d75e32fe6 100644
--- a/app/templates/views/uploads/choose-file.html
+++ b/app/templates/views/uploads/choose-file.html
@@ -21,7 +21,7 @@
     )}}
   </p>
   <p>You can upload a single letter as a PDF.</p>
-  <p>Your file must meet our <a href="https://docs.notifications.service.gov.uk/documentation/images/notify-pdf-letter-spec-v2.3.pdf">letter specification</a>.</p>
+  <p>Your file must meet our <a href="https://docs.notifications.service.gov.uk/documentation/images/notify-pdf-letter-spec-v2.4.pdf">letter specification</a>.</p>
 
   </div>
 </div>