diff --git a/mypy.ini b/mypy.ini
index 95ec22d65be..ad916185bce 100644
--- a/mypy.ini
+++ b/mypy.ini
@@ -39,3 +39,8 @@ ignore_missing_imports = True
 
 [mypy-_black_version.*]
 ignore_missing_imports = True
+
+# CI only checks src/, but in case users are running LSP or similar we explicitly ignore
+# errors in test data files.
+[mypy-tests.data.*]
+ignore_errors = True