diff --git a/CHANGES.md b/CHANGES.md
index bdeb614b9e9b5d84c6e5420184d1d7cb8e053ccd..206859cff7eee97d917cd2e6d91ac4d12128df63 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,12 @@
+Synapse 1.33.0 (2021-05-05)
+===========================
+
+Features
+--------
+
+- Build Debian packages for Ubuntu 21.04 (Hirsute Hippo). ([\#9909](https://github.com/matrix-org/synapse/issues/9909))
+
+
Synapse 1.33.0rc2 (2021-04-29)
==============================
diff --git a/debian/changelog b/debian/changelog
index fd33bfda5c1ca9da42ea277a65d75ae4d80ec226..b54d3f2bc6402597a4c8b9bd8d33b2aca29384c7 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+matrix-synapse-py3 (1.33.0) stable; urgency=medium
+
+ * New synapse release 1.33.0.
+
+ -- Synapse Packaging team <packages@matrix.org> Wed, 05 May 2021 14:15:27 +0100
+
matrix-synapse-py3 (1.32.2) stable; urgency=medium
* New synapse release 1.32.2.
diff --git a/scripts-dev/build_debian_packages b/scripts-dev/build_debian_packages
index 3bb6e2c7ea80d5d9c8d8cc612371ee46f934d882..07d018db9985f1ed2ffcbde603460b0634c775fb 100755
--- a/scripts-dev/build_debian_packages
+++ b/scripts-dev/build_debian_packages
@@ -21,9 +21,10 @@ DISTS = (
"debian:buster",
"debian:bullseye",
"debian:sid",
- "ubuntu:bionic",
- "ubuntu:focal",
- "ubuntu:groovy",
+ "ubuntu:bionic", # 18.04 LTS (our EOL forced by Py36 on 2021-12-23)
+ "ubuntu:focal", # 20.04 LTS (our EOL forced by Py38 on 2024-10-14)
+ "ubuntu:groovy", # 20.10 (EOL 2021-07-07)
+ "ubuntu:hirsute", # 21.04 (EOL 2022-01-05)
)
DESC = '''\
diff --git a/synapse/__init__.py b/synapse/__init__.py
index 319c52be2c4929c605790333791098423f531fef..5eac40730a7719fdc2cbb39de4c52a6f0ba4aace 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -47,7 +47,7 @@ try:
except ImportError:
pass
-__version__ = "1.33.0rc2"
+__version__ = "1.33.0"
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