Clean up stale Git remote-tracking branches

Use git fetch --prune origin to remove obsolete remote-tracking refs for origin under the normal branch refspec. Local branches such as feature-x are separate refs and remain until you delete them explicitly.

Prune the remote-tracking refs

git fetch --prune origin
# Preview a prune without fetching new objects:
git remote prune --dry-run origin
# Apply that prune:
git remote prune origin

To enable pruning for future fetches in this repository:

git config --local fetch.prune true

Use --global only if you intentionally want the same default in other repositories. Pruning follows the configured refspecs: explicit tag or other destination mappings can broaden what is removed. Inspect custom mappings before assuming the operation affects only origin/*.

Inspect local branches with missing upstreams

git branch -vv
git for-each-ref \
  --format='%(refname:short) %(upstream:short) %(upstream:track)' \
  refs/heads/

A [gone] indication means the configured upstream ref is missing locally. After a successful fetch, that often reflects a deleted remote branch, but it does not establish that all local work was integrated elsewhere.

Avoid piping the first word of git branch -vv directly into deletion commands. Its display includes markers for checked-out branches and worktrees, and a missing upstream is only a review signal.

Verify and delete one branch

git log --oneline main..feature-x
git branch --merged main
git branch -d feature-x

Check against the intended integration target, using an updated remote-tracking ref if appropriate. -d checks the branch's upstream when available, or HEAD when no upstream is set; an unresolved configured upstream can cause deletion to be refused. It is not a universal guarantee that a branch is merged into main.

If Git refuses deletion, inspect the history. Preserve needed commits with another branch or tag. Use -D only after confirming that removing the ref is intentional; it bypasses the normal merged-history check. A branch checked out in another worktree needs separate attention.

Keep cleanup manageable

A hosting service may offer automatic deletion of merged pull-request branches. That removes the remote branch, not every developer's local copy. Pair it with regular fetch/prune and deliberate local review. Pruning compares advertised refs with local mappings; its cost depends on the remote and repository, so avoid promises of zero overhead.

See git-fetch pruning, git-remote, and git-branch.