Under the SkyMiles Mileage Expiration policy, miles do not expire. Delta reserves the right to deactivate or close an account under the following circumstances: Fraudulent activity occurs. A Member requests an account closure.

No, Delta SkyMiles do not expire. This has been a core feature of the program for years and remains true in 2026. Unlike some other airline loyalty programs that require you to have "account activity" (earning or spending miles) at least once every 12 to 24 months, Delta miles stay in your account indefinitely as long as the account remains open. This makes SkyMiles a "safe" currency for casual travelers who might only fly once every few years. However, there is a small catch: Delta reserves the right to close an account (and thus forfeit the miles) if there is fraudulent activity or if the account has been completely inactive for an exceptionally long time (usually several years of no login or contact), though this is rare. Even though the miles don't expire, their purchasing power can change; airlines frequently adjust the "price" of award tickets (inflation), so a flight that costs 20,000 miles today might cost 30,000 miles in three years. For this reason, travel experts still recommend a "earn and burn" strategy rather than hoarding miles for decades.