Go to the United Airlines Mileage Plus website at ualmiles.com to buy or transfer extra miles. Miles can only be purchased online on United Airlines' website.
Click on the purchase option that matches your needs. Customers can purchase miles for themselves, as a gift, or for business appreciation gifts. Miles can also transferred between accounts or reinstated from the United Airlines Mileage Plus website.
Select the number of miles you would like to purchase from the drop-down menu. Miles can be purchased in multiples of 1,000.
Fill out the order form to process your order. You must have your Mileage Plus account number, along with a valid credit card, to process the order request. Once all the information has been entered correctly, your order will be submitted.