Q. I am ashamed to admit that in all of my years of mostly international travel that I have never once used my miles to upgrade, which I think is a mistake. I am very tired of economy class although economy plus is okay. My question is can I purchase a ticket to Bangkok from anyone & upgrade it with United or do I need to specifically purchase it from United? What to do?

A. You definitely need to purchase the fare from United or a United partner airline. The number of miles needed will depend on the date of travel and perhaps the routing, and also the fare you pay. It's sometimes a good idea to call the United MileagePlus helpline (1-800-421-4655) and consult a reservation agent to determine which fares and flights are eligible or available for upgrades.

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