! [rejected]: git push rejected (non-fast-forward)

The remote branch has commits you do not have. Integrate them with pull or rebase, then push — do not force over other people's work.

What happened

You ran git push and Git refused to update the remote branch. The output marks the ref with ! and the word rejected.

git push output (illustrative)Illustrative example

$ git push origin main
To github.com:mainframe-learner/mp-batch-jobs.git
 ! [rejected]        main -> main (fetch first)
error: failed to push some refs to 'github.com:mainframe-learner/mp-batch-jobs.git'
hint: Updates were rejected because the remote contains work that you do not
hint: have locally.

What it means

A push is a fast-forward when your new commit descends from the commit the remote branch points to now. If someone else pushed in the meantime, the remote has commits you lack. Accepting your push would drop them from the branch's history, so Git refuses by default.

In the push output, ! marks a ref that was not updated. rejected means your Git never sent the update, usually because it is not a fast-forward. remote rejected means the server refused it — for example because of a hook, branch protection, or a setting such as receive.denyNonFastForwards.

Typical causes

A teammate pushed to the same branch since your last fetch or pull.
You amended or rebased commits that were already pushed, so your history now differs from the remote.
A CI job or bot committed to the branch (version bumps, generated files).

Symptoms

Push fails; your commits stay local.
git status shows your branch and its upstream have diverged after a git fetch.

Where to look

The push output: the reason in brackets and whether it says rejected or remote rejected.
git fetch then git log --oneline main..origin/main to see the commits you are missing.
The repository's branch protection settings on GitHub if it was a remote rejection.

How to diagnose

Run git fetch to update your view of the remote.
Compare local and remote with git log --oneline --graph --all or the two-dot ranges above.
Decide: are the remote commits someone else's real work (integrate them) or your own old version of rewritten history?

How to fix

Integrate by merging: git pull, resolve any conflicts, then git push.
Or integrate by rebasing: git pull --rebase, resolve conflicts, then git push — this keeps a straight history.
Only if you intentionally rewrote your own branch and nobody else uses it: git push --force-with-lease. It overwrites the remote only if it still points where your remote-tracking branch says, so it will not silently delete commits you have not seen.

git push rejected (non-fast-forward)