With most airlines, free flights generally start at 5,000 to 7,500 miles per one-way segment. So to book a round-trip flight, you typically need at least 10,000 to 15,000 miles. But prices that low tend to only be available on short hops, meaning flights of about an hour to an hour and a half.
Most airlines allow travelers to redeem their miles for flights, seat upgrades, or other travel-related perks, but they don't convert them directly to cash. Some airlines also permit the transfer of miles to other reward programs, such hotel loyalty programs, which may include the option of cash redemption.
United award flight prices vary substantially based on the cabin class and when you're flying. Example: Economy Saver Award prices for the short hop from San Francisco to Los Angeles run as low as 5,100 miles, while a first-class Everyday Award for the same hop costs around 30,000 miles.
You cannot convert American miles to cash. However, you can redeem your miles for Admirals Club memberships, rental cars and hotel stays, vacation packages, luxury experiences, and donations to partner charities.
Miles and points earned on co-branded hotel and airline travel rewards cards do expire usually if you are not active in redeeming them for 12 to 24 months, depending on the terms of the hotel or airline loyalty program.
To figure out the number of cents per point or mile you'll get from a specific redemption, divide the cash price of the award by the number of points or miles needed. For example, if an award flight that requires 25,000 miles to book would cost $500 if you paid cash, $500 / 25,000 = 2 cents per mile.