While British Airways and the International Airlines Group (IAG) officially prohibit the "buying, selling, or bartering" of Avios points in their terms and conditions—threatening to close accounts that do so—a thriving "grey market" of mileage brokers exists in 2026. To sell them, you typically go through a third-party platform like MilesBuyer or SellMyMiles. The process involves submitting a quote for your points (usually requiring a minimum of 50,000 to 100,000), providing your account details, and receiving payment via PayPal or bank transfer once the broker "uses" your points to book a ticket for another client. Be warned: this carries a high risk. If the airline detects the transaction (which they often do via "audit" algorithms), they can instantly cancel the tickets and permanently ban your Executive Club account, resulting in the loss of all remaining miles. A safer, "legal" alternative is to use your Avios to book flights for friends or family, which is explicitly allowed, or to "Boost" your points through the official BA portal if you are looking to increase your balance rather than liquidate it for cash.