?Request flight credit Requests may be submitted up to one year after the date of your flight. For United-operated flights, you only need to enter the 13-digit ticket number. If you have more than four flight segments on your itinerary, you need to enter each ticket number.

For United Airlines MileagePlus members, the window to claim "missing" miles for a flight you have already taken is generally 12 months from the date of travel. This applies to United-operated flights as well as most Star Alliance partner flights. However, there is a catch: if you were not a member of the MileagePlus program at the time of the flight, you typically only have 30 to 90 days after your flight to join the program and request credit for that specific trip. To make a claim, you usually need your ticket number (a 13-digit code starting with 016 for United) and your boarding pass. It is worth noting that while you have a year to claim them, it can take up to 15 days for miles to post automatically, so United recommends waiting at least two weeks after travel before filing a formal "missing miles" request through their website or app.