: Avoid "mileage brokers." Buying miles from anyone other than the airline directly violates terms of service and can result in your account being permanently closed. A Guide to Buying Airline Miles: When to Buy, When to Skip
: Buying miles during a sale (e.g., a 70%–140% bonus) can sometimes be cheaper than paying cash for a business or first-class seat. For example, buying $2,000 worth of miles to book a $10,000 first-class ticket provides massive outsized value. how much does it cost to buy air miles
: Airlines can change the "price" of award seats at any time without notice, making your purchased miles less valuable overnight. : Avoid "mileage brokers