diff --git a/.prettierignore b/.prettierignore
index 1df536988..00f921c44 100644
--- a/.prettierignore
+++ b/.prettierignore
@@ -2,6 +2,11 @@
 # formatting. Prettier must not reformat it, or `catalog:check` (the drift gate) fails.
 packages/webkit/catalog.json
 
+# Generated by release-please (committed via the GitHub API on the Release PR —
+# no local hook ever runs on it, and its markdown style differs from Prettier's).
+# The generator is the single source of formatting.
+**/CHANGELOG.md
+
 # Lint canaries are DELIBERATELY rule-breaking / mis-formatted fixtures that
 # must KEEP failing their lint (see lint-canaries/README.md). A repo-wide
 # `prettier --write` must never "fix" them. The canary runner itself bypasses