GitHub PR Reviews: Comment vs. Approve vs. Request Changes – When to Use Each

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Code reviews are a critical part of collaborative software development, and GitHub provides three key options when reviewing a pull request (PR): Comment, Approve, and Request Changes. Understanding the differences between these options ensures smooth collaboration and prevents unnecessary bottlenecks.

This guide explains each review action, when to use them, and best practices for effective code reviews.

1. Comment – Neutral Feedback

What It Does

Submits general feedback without approving or blocking the PR.
Does not affect the PR’s ability to be merged.

When to Use It

✅ Non-blocking suggestions (e.g., "Consider renaming this variable for better readability.")

✅ Questions (e.g., "How does this handle edge case X?")

✅ Minor nitpicks that don’t require changes before merging

Example Scenario

"This function works, but adding a short comment explaining the logic would help future maintainers. Otherwise, looks good!"

2. Approve – Green Light to Merge

What It Does

Officially approves the PR, allowing it to be merged (if branch protection rules permit).
Can still include feedback (e.g., minor suggestions that don’t block approval).

When to Use It

✅ The PR meets all requirements and is ready to merge.

✅ You agree with the changes, even if there are small, non-critical improvements.

Example Scenario

"Approved! The refactor looks clean, and tests pass. One minor suggestion: we could add a log message for debugging, but it’s not blocking."

3. Request Changes – Blocking Feedback

What It Does

Prevents the PR from being merged until the reviewer’s concerns are resolved.
Requires the author to make updates and re-request review.

When to Use It

🚨 Critical bugs or security vulnerabilities.

🚨 Major deviations from coding standards or architecture guidelines.

🚨 Missing tests, documentation, or key functionality.

Example Scenario

"Requesting changes: This PR introduces a race condition in the payment processing logic. Let’s add a mutex lock or revise the approach before merging."

Key Differences at a Glance

Review Action	Blocks Merge?	Best For
Comment	❌ No	Discussions, minor suggestions, questions.
Approve	❌ No	Approving merges (with or without minor notes).
Request Changes	✅ Yes	Mandatory fixes before merging.

Best Practices for Effective Reviews

1. Use "Request Changes" Judiciously

Overusing it can slow down development. Reserve it for high-impact issues.
For minor tweaks, use Comment + Approve instead.

2. Be Clear and Constructive

Instead of "This is wrong," say "Let’s refactor this to avoid X issue because…"
Link to docs or prior discussions for context.

3. Resolve Stale Reviews

If a PR is updated after a Request Changes, dismiss the old review or re-review.

4. Follow Team Conventions

Some teams require multiple approvals before merging.
Others use Comment for async discussions before approval.

Conclusion

Choosing the right GitHub review action—Comment, Approve, or Request Changes—helps maintain a balance between collaboration and code quality.