diff --git a/CHANGES.md b/CHANGES.md
index 6618378c060849c785f00e85ea62635baf236fc8..58775e351940bd6d99a063643c23961f30b25a9b 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,14 @@
+Synapse 1.55.1 (2022-03-24)
+===========================
+
+This is a patch release that fixes an incompatibility with version 3.1.0 of the Jinja2 library, released on March 24th, 2022. Deployments of Synapse using the official Docker images or Debian packages are not affected.
+
+Internal Changes
+----------------
+
+- Remove uses of the long-deprecated `Jinja2.Markup` which would prevent Synapse from starting with Jinja2 3.1.0 or above installed. ([\#12289](https://github.com/matrix-org/synapse/issues/12289))
+
+
 Synapse 1.55.0 (2022-03-22)
 ===========================
 
diff --git a/changelog.d/12289.misc b/changelog.d/12289.misc
deleted file mode 100644
index f80ccf3284cd1b6604ba246f0bcd4e2c3cdb86dd..0000000000000000000000000000000000000000
--- a/changelog.d/12289.misc
+++ /dev/null
@@ -1 +0,0 @@
-Remove uses of the long-deprecated `Jinja2.Markup` which would prevent Synapse from starting with Jinja2 3.1.0 or above installed. This does not affect deployments of Synapse using our Docker images or Debian packages.
\ No newline at end of file
diff --git a/debian/changelog b/debian/changelog
index 7eed6c5b4a1acb72cc47cdbf1c7d886109d2c3e4..f3ac279302fd15bc3ec3d4eda14bee91f9b1d933 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+matrix-synapse-py3 (1.55.1) stable; urgency=medium
+
+  * New synapse release 1.55.1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Thu, 24 Mar 2022 17:44:23 +0000
+
 matrix-synapse-py3 (1.55.0) stable; urgency=medium
 
   * New synapse release 1.55.0.
diff --git a/synapse/__init__.py b/synapse/__init__.py
index f0f224d0bb4eb611644b34916f21ffcdee57638f..70f56824f98883777b3ce593048b6e7d556048c8 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -68,7 +68,7 @@ try:
 except ImportError:
     pass
 
-__version__ = "1.55.0"
+__version__ = "1.55.1"
 
 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