Emphatically, yes, but if you're changing it for vanity reasons, it may not matter too much, especially if there's some type of misspelling. Most airlines and security are pretty easygoing enough (I know).
The name on the flight does matter if you are trying to credit miles to a partner airline, though. In order to do so, most travelers will need to contact a gate agent or a reservation agent.
In my case, I was trying to credit a United flight to Asiana Club, and my Asiana number was just not registering because of a name "mismatch." (This had also happened on a previous Detroit flight, so I was aware of this going in.)
I called United to rectify the problem-I may have their number on speed dial-and the phone agent was able to remove my middle name, solving the issue.
She did note, however, that names changes sometimes deselect seat selections. Mine remained fine.
Because I really need all of those miles. ⭐
