Delta miles do not expire as long as the Delta account is open and in good standing. The only time Delta miles expire is when you or Delta closes the account without first redeeming unused rewards.

The best news for travelers in 2026 is that you actually don't need to do anything to keep your Delta SkyMiles from expiring. Delta Air Lines was one of the first major carriers to eliminate mileage expiration entirely. As long as your SkyMiles account remains open, your miles are yours to keep for a lifetime, regardless of how often you fly or use your account. This "no expiration" policy applies to all members globally. However, while the miles themselves won't disappear, it is still a "best practice" to engage with the program to keep your account active and avoid any potential security-related deactivation of dormant accounts. You can do this by flying with Delta or its SkyTeam partners, using a co-branded Delta American Express card for daily purchases, or earning miles through the SkyMiles Dining or Shopping portals. Even if you don't fly for five years, your balance will remain intact. This makes SkyMiles one of the most consumer-friendly loyalty currencies in 2026, allowing you to save up for a "bucket list" trip over a decade without the stress of a ticking clock.