What is a merged question?

A merged question is a question where a moderator has chosen to move its answers to another question, because it is an exact duplicate of another and has good answers that would be useful on the target. Merged questions are also locked to prevent edits.

Questions should be merged if one question is an exact duplicate of another (i.e., when its answers would make perfect sense on the other question), and its answers are high-quality and valuable enough to be included on the other question itself, so that good answers aren't forked across multiple copies of the same question.

In order to merge a question, the question to be merged must first be closed as a duplicate of the intended merge target.

Note that the only significant benefit that merging offers over just closing a question as a duplicate is that it moves the answers from the merged question over to the main question. If there are no useful or valuable answers to be preserved, there is no point in merging the question, and requests to do so will likely be declined.

Only moderators can merge questions. If you believe a question should be merged, first vote or recommend closure flag to close it as a duplicate, and wait until the question gets closed as a duplicate. Once it is (or if it already is), flag the question for moderator attention, clearly explaining that the question should be merged and that it fits the guidelines in the above section.

All of the merged question's answers, including their votes and comments, become answers to the target question. Non-deleted comments on the merged question are moved to the target question.

Users who bookmarked (favorited or starred) the merged question will be automatically bookmarked to the target question.

The following is added to the edit history:

Post Merged (destination) from example.com

The merge stub question is locked to prevent edits to its content that would make the merge no longer make sense. If you need to make edits to it for any reason (e.g. it uses a tag being removed as part of a community cleanup, it has a broken link serving malware, etc.), flag it for moderator attention and clearly explain the problem.

As merged questions are locked, they are exempt from the Roomba autodeletion criteria as those exclude locked questions (except those locked as migration stubs or rejected migrations).

Votes on the merged question do not get imported into the master question

If a question with answers is merged into a community wiki question, the answers will not be automatically converted to community wiki.

If a merge stub that was originally migrated from another site is deleted, it does not cause the migration to be marked "rejected" as it normally would in most cases.

User reputation is unaffected when a question is merged. Users who asked or answered the merged question retain their reputation as-is. Answers to the merged question can gain additional reputation after getting migrated to the target question.

If the merge stub is later deleted, the asker will lose the reputation they earned from it unless it had a score of at least 3 and was visible for at least 60 days (the normal criteria for reputation retention).

If the merge stub has an accepted answer, it is unaccepted when it is moved to the target question.

Prior to June 2010, a stub was not left behind when merging questions, and instead the original question was hard-deleted (removed from the database, not visible to 10k+ users).