diff --git a/templates.py b/templates.py
index 2ebabff..5104d73 100644
--- a/templates.py
+++ b/templates.py
@@ -140,6 +140,10 @@ def update(args: argparse.Namespace) -> None:
     for file in answers:
         run_update(".", answers_file=str(file), unsafe=True, overwrite=True,
                    skip_answered=not args.ask, defaults=args.defaults, vcs_ref=REF)
+        conflicts = subprocess.run(["git", "diff", "--name-only", "--diff-filter=U"],
+                                   capture_output=True, text=True, check=False).stdout.split()
+        if conflicts:
+            sys.exit(f"{file.stem}: resolve conflicts, then commit and rerun:\n  " + "\n  ".join(conflicts))
         refresh_locks(file.stem)
         if git_dirty():
             subprocess.run(["git", "add", "-A"], check=True)