diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 955beb4aa..7c2f7d4b1 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -322,7 +322,7 @@ jobs:
         working-directory: complement/dockerfiles
 
       # Run Complement
-      - run: go test -v -tags synapse_blacklist ./tests
+      - run: go test -v -tags synapse_blacklist,msc2403,msc2946,msc3083 ./tests
         env:
           COMPLEMENT_BASE_IMAGE: complement-synapse:latest
         working-directory: complement
diff --git a/changelog.d/10155.misc b/changelog.d/10155.misc
new file mode 100644
index 000000000..27b98e7fe
--- /dev/null
+++ b/changelog.d/10155.misc
@@ -0,0 +1 @@
+Update the Complement build tags in GitHub Actions to test currently experimental features.
\ No newline at end of file