diff --git a/.github/actions/rename_towncrier/rename_towncrier.py b/.github/actions/rename_towncrier/rename_towncrier.py
new file mode 100755
index 00000000000..68971d1c83f
--- /dev/null
+++ b/.github/actions/rename_towncrier/rename_towncrier.py
@@ -0,0 +1,56 @@
+#!/usr/bin/env python3
+
+# Adapted from action-towncrier-changelog
+import json
+import os
+import re
+import subprocess
+import sys
+from pathlib import Path
+
+from github import Github
+from tomllib import loads
+
+event_name = os.getenv('GITHUB_EVENT_NAME', 'pull_request')
+if not event_name.startswith('pull_request'):
+    print(f'No-op for {event_name}')
+    sys.exit(0)
+if 'GITHUB_EVENT_PATH' in os.environ:
+    with open(os.environ['GITHUB_EVENT_PATH'], encoding='utf-8') as fin:
+        event = json.load(fin)
+    pr_num = event['number']
+    basereponame = event['pull_request']['base']['repo']['full_name']
+    real = True
+else:  # local testing
+    pr_num = 12318  # added some towncrier files
+    basereponame = "mne-tools/mne-python"
+    real = False
+
+g = Github(os.environ.get('GITHUB_TOKEN'))
+baserepo = g.get_repo(basereponame)
+
+# Grab config from upstream's default branch
+toml_cfg = loads(Path("pyproject.toml").read_text("utf-8"))
+
+config = toml_cfg["tool"]["towncrier"]
+pr = baserepo.get_pull(pr_num)
+modified_files = [f.filename for f in pr.get_files()]
+
+# Get types from config
+types = [ent["directory"] for ent in toml_cfg["tool"]["towncrier"]["type"]]
+type_pipe = "|".join(types)
+
+# Get files that potentially match the types
+directory = toml_cfg["tool"]["towncrier"]["directory"]
+assert directory.endswith("/"), directory
+
+file_re = re.compile(rf"^{directory}({type_pipe})\.rst$")
+found_stubs = [
+    f for f in modified_files if file_re.match(f)
+]
+for stub in found_stubs:
+    fro = stub
+    to = file_re.sub(rf"{directory}{pr_num}.\1.rst", fro)
+    print(f"Renaming {fro} to {to}")
+    if real:
+        subprocess.check_call(["mv", fro, to])
diff --git a/.github/workflows/autofix.yml b/.github/workflows/autofix.yml
new file mode 100644
index 00000000000..2c0b693750e
--- /dev/null
+++ b/.github/workflows/autofix.yml
@@ -0,0 +1,21 @@
+name: autofix.ci
+
+on:  # yamllint disable-line rule:truthy
+  pull_request:
+    types: [opened, synchronize, labeled, unlabeled]
+
+permissions:
+  contents: read
+
+jobs:
+  autofix:
+    name: Autoupdate changelog entry
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
+      - run: pip install --upgrade towncrier pygithub
+      - run: python ./.github/actions/rename_towncrier/rename_towncrier.py
+      - uses: autofix-ci/action@ea32e3a12414e6d3183163c3424a7d7a8631ad84
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index fed7db76310..f23220d9819 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -59,6 +59,3 @@ repos:
         # Avoid the conflict between mne/__init__.py and mne/__init__.pyi by ignoring the former
         exclude: ^mne/(beamformer|channels|commands|datasets|decoding|export|forward|gui|html_templates|inverse_sparse|io|minimum_norm|preprocessing|report|simulation|source_space|stats|time_frequency|utils|viz)?/?__init__\.py$
         additional_dependencies: ["numpy==1.26.2"]
-
-ci:
-  autofix_prs: false
diff --git a/doc/changes/devel/12318.other.rst b/doc/changes/devel/12318.other.rst
new file mode 100644
index 00000000000..94890e1dfc4
--- /dev/null
+++ b/doc/changes/devel/12318.other.rst
@@ -0,0 +1 @@
+Automate adding of PR number to towncrier stubs, by `Eric Larson`_.