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https://www.united.com/ual/en/us/mil...mileagecredit/Request flight credit
You may request credit for up to four flight segments at one time. Requests may be submitted up to 12 months 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 flights operated by an airline partner, you'll also enter the 13-digit ticket number. If the ticket number is available in our system, then the flight information will be presented for you to submit. If the ticket information is not in our system, you'll need to enter additional information along with the ticket number.The required information is located on your boarding pass stub and ticket receipt and should be entered exactly as displayed on the document.To request credit you must first
sign in to your MileagePlus account.