How to Require Status Checks with Branch Protection

Required status checks live in branch protection and block a merge; a badge only displays a result and enforces nothing.

Add a branch protection rule that lists the checks that must pass. The check name is the job name reported to the commit. A badge on the README shows status but has no effect on merges.

Steps

Open Settings to Branches and add a rule for main.
Enable "Require status checks to pass before merging".
Select the check by its job name (it appears after it has run once).

The job whose name becomes the check

.github/workflows/ci.yml

jobs:
  build-and-test:
    name: build-and-test
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: npm ci && npm test

Badge vs check

A badge is a read-only image; anyone can see it but it never blocks anything.
A required status check is enforcement configured in branch protection, keyed on the check name.
A green badge with a broken required check still blocks the merge, and vice versa.

Gotchas

A check must run at least once before it appears in the selection list.
Renaming a job changes the check name and silently drops it from the required list.