diff --git a/changelog.d/17403.feature b/changelog.d/17403.feature
new file mode 100644
index 000000000..b1868d760
--- /dev/null
+++ b/changelog.d/17403.feature
@@ -0,0 +1 @@
+Declare support for [Matrix 1.11](https://matrix.org/blog/2024/06/20/matrix-v1.11-release/).
\ No newline at end of file
diff --git a/synapse/rest/client/versions.py b/synapse/rest/client/versions.py
index e01e5f542..84cf388bd 100644
--- a/synapse/rest/client/versions.py
+++ b/synapse/rest/client/versions.py
@@ -102,6 +102,7 @@ class VersionsRestServlet(RestServlet):
                     "v1.8",
                     "v1.9",
                     "v1.10",
+                    "v1.11",
                 ],
                 # as per MSC1497:
                 "unstable_features": {