diff --git a/CHANGES.md b/CHANGES.md
index c216d288180c438dbf450d647e2990834554e317..d584d342d75c86e84c2f18ffa141b58faff1642b 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,10 +1,20 @@
-Synapse 1.28.0rc1 (2021-02-19)
-==============================
+Synapse 1.28.0 (2021-02-25)
+===========================
 
 Note that this release drops support for ARMv7 in the official Docker images, due to repeated problems building for ARMv7 (and the associated maintenance burden this entails).
 
 This release also fixes the documentation included in v1.27.0 around the callback URI for SAML2 identity providers. If your server is configured to use single sign-on via a SAML2 IdP, you may need to make configuration changes. Please review [UPGRADE.rst](UPGRADE.rst) for more details on these changes.
 
+
+Internal Changes
+----------------
+
+- Revert change in v1.28.0rc1 to remove the deprecated SAML endpoint. ([\#9474](https://github.com/matrix-org/synapse/issues/9474))
+
+
+Synapse 1.28.0rc1 (2021-02-19)
+==============================
+
 Removal warning
 ---------------
 
@@ -31,7 +41,7 @@ Bugfixes
 --------
 
 - Fix long-standing bug where sending email notifications would fail for rooms that the server had since left. ([\#9257](https://github.com/matrix-org/synapse/issues/9257))
-- Fix bug in Synapse 1.27.0rc1 which meant the "session expired" error page during SSO registration was badly formatted. ([\#9296](https://github.com/matrix-org/synapse/issues/9296))
+- Fix bug introduced in Synapse 1.27.0rc1 which meant the "session expired" error page during SSO registration was badly formatted. ([\#9296](https://github.com/matrix-org/synapse/issues/9296))
 - Assert a maximum length for some parameters for spec compliance. ([\#9321](https://github.com/matrix-org/synapse/issues/9321), [\#9393](https://github.com/matrix-org/synapse/issues/9393))
 - Fix additional errors when previewing URLs: "AttributeError 'NoneType' object has no attribute 'xpath'" and "ValueError: Unicode strings with encoding declaration are not supported. Please use bytes input or XML fragments without declaration.". ([\#9333](https://github.com/matrix-org/synapse/issues/9333))
 - Fix a bug causing Synapse to impose the wrong type constraints on fields when processing responses from appservices to `/_matrix/app/v1/thirdparty/user/{protocol}`. ([\#9361](https://github.com/matrix-org/synapse/issues/9361))
diff --git a/debian/changelog b/debian/changelog
index aa83d4e13e83dc10616c15dfee41c918b02cd4ee..642e4d381d2427519d8d3b96db5bf868c659323c 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+matrix-synapse-py3 (1.28.0) stable; urgency=medium
+
+  * New synapse release 1.28.0.
+
+ -- Synapse Packaging team <packages@matrix.org>  Thu, 25 Feb 2021 10:21:57 +0000
+
 matrix-synapse-py3 (1.27.0) stable; urgency=medium
 
   [ Dan Callahan ]
diff --git a/synapse/__init__.py b/synapse/__init__.py
index 2e70f46186a40fb724b3513a83b036f4e4a464f1..869e860fb045eeec56e6468ba5143531a33ec9bc 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -48,7 +48,7 @@ try:
 except ImportError:
     pass
 
-__version__ = "1.28.0rc1"
+__version__ = "1.28.0"
 
 if bool(os.environ.get("SYNAPSE_TEST_PATCH_LOG_CONTEXTS", False)):
     # We import here so that we don't have to install a bunch of deps when
diff --git a/synapse/rest/synapse/client/__init__.py b/synapse/rest/synapse/client/__init__.py
index 8588b6d271cc0fbc3a6697d72218a7cf954f401c..9eeb970580edf26aae262aba8dd8cea47c0d05af 100644
--- a/synapse/rest/synapse/client/__init__.py
+++ b/synapse/rest/synapse/client/__init__.py
@@ -54,7 +54,12 @@ def build_synapse_client_resource_tree(hs: "HomeServer") -> Mapping[str, Resourc
     if hs.config.saml2_enabled:
         from synapse.rest.synapse.client.saml2 import SAML2Resource
 
-        resources["/_synapse/client/saml2"] = SAML2Resource(hs)
+        res = SAML2Resource(hs)
+        resources["/_synapse/client/saml2"] = res
+
+        # This is also mounted under '/_matrix' for backwards-compatibility.
+        # To be removed in Synapse v1.32.0.
+        resources["/_matrix/saml2"] = res
 
     return resources