MX records and email migration: when do you change them?
Do you have to change your MX records when migrating email? Not always. This explainer tells you exactly when you do and when you do not.
What MX records do
MX records tell the rest of the world which server email for your domain should be sent to. If you change mail provider for your own domain, those records still point to the old server until you change them.
Do change them: you are moving domain email
If you switch to a new provider for mail on your own domain, you change the MX records so new mail arrives on the new server. Do this only after the migration of existing mail is finished.
Do not change them: only copying mail
If you only copy existing messages from, say, Gmail to another address without moving your domain, you do not touch DNS. The migration itself does not affect your MX records — that step only comes into play with an actual domain move.