Do Airline Miles Expire? Delta, American and the Details

• No expiration

  Delta states SkyMiles do not expire, per its official program rules reviewed on 11 August 2026

• Every 24 months

  American requires qualifying earning or redemption activity every 24 months for most adult accounts, with stated exceptions

• No expiration

  Southwest states Rapid Rewards points do not expire, although closing the account forfeits them

• Separate from tickets

  Miles expiration differs from the rules of an issued award ticket

“Do airline miles expire?” has to be answered program by program, because the programs reviewed for this guide do not share one rule. Delta states that SkyMiles do not expire, and Southwest says the same of Rapid Rewards points. American’s AAdvantage terms, by contrast, require qualifying earning or redemption activity every 24 months to keep most adult accounts’ miles alive, with exceptions spelled out in the terms. Neither of those is a guess; each traces to the airline’s own page.

A second distinction matters just as much. Miles expiring is one thing; an award ticket you have already issued is another; and a flight or travel credit is a third. People lose real money by confusing the three, so this guide keeps them separate and explains where each lives. As of 11 August 2026, your safest move is to read the rule for the program that actually holds your balance.

Delta: SkyMiles do not expire

Delta’s official SkyMiles program rules, reviewed on 11 August 2026, state that SkyMiles do not expire. That is a direct statement from Delta, and it is the headline a lot of travelers want: a Delta balance is not racing a clock just because you have not flown or earned recently. That does not remove the need to keep the account in good standing.

The practical implication of the no-expiration rule is that a Delta balance you are saving does not lapse through simple inactivity alone. But program rules can be revised, and account status or closure can change the picture even where miles do not expire by themselves. So treat Delta’s statement as current guidance, not a permanent guarantee, and check the official rules page if your account ever changes status.

Because Delta’s position is so much more forgiving than American’s, it is tempting to assume every program works the same way. It does not, and that is exactly the kind of assumption this guide pushes back on rather than repeating.

American: the 24-month activity rule

American’s AAdvantage terms, reviewed on 11 August 2026, describe the miles-expiration rule as an activity requirement: miles for most adult accounts expire if there is no qualifying earning or redemption activity within a 24-consecutive-month period. In plain terms, the clock is not a fixed deadline you can ignore; it is a rolling window that resets around qualifying activity.

The exceptions matter. American’s reviewed terms exempt members under age 21 and qualifying primary AAdvantage credit cardmembers while the card account remains open. Those conditions may not cover every account that looks similar, so apply the current official wording to your own status before assuming the 24-month rule does—or does not—apply.

For a comparison of what a balance is actually worth when you do use it, the points redemption value guide is a useful companion, but protecting the balance from expiration is a separate job handled by activity, not by redemption value.

Southwest does not expire; verify United

Southwest’s current terms directly state that points do not expire and that closing an account forfeits its points. This dated audit leaves United as the verify row rather than inferring a rule it did not establish with the same confidence. Read United’s live rules before relying on a MileagePlus balance.

Miles expiration vs award ticket rules

Miles expiring is a loyalty-program rule about whether your balance stays alive. An award ticket’s rules are about whether a specific issued ticket remains usable, under its own fare conditions, once you have already redeemed miles for it. These are different systems, and the same program can let a balance sit for years while an individual ticket has its own validity window.

In practice, that means a miles balance that is safe from expiration tells you nothing about the ticket you already issued, and vice versa. If you have an award ticket with a change or travel window, track that ticket on its own terms rather than assuming your safe balance extends its validity. The award ticket booking question is separate from account balance protection.

Keeping the two labels straight also prevents a bad call: someone who holds a balance with no expiration might still hold an award ticket that has already lapsed, or a ticket with cash value that is about to. The protection you need is different for each one.

Miles expiration vs flight and travel credit

A flight or travel credit is a monetary credit with its own expiry, set by the airline as part of its cancellation policy, and it is not the same thing as your miles balance. Miles expiring is about your loyalty balance staying alive, while a credit expiring is about a specific amount the airline holds for a future booking. The two run on different timetables and rules.

This distinction is where travelers most often trip up. You might keep a miles balance alive for years only to discover that an unrelated flight credit, earned from a cancelled ticket, has a much shorter and already-expiring window. Track each separately: the balance against its program rule, and the credit against the airline’s stated validity. For the credit side specifically, the how to use flight credit guide walks through redeeming that value before its deadline.

What counts as qualifying activity

Qualifying activity is what keeps a balance alive on a program like American’s, and what counts is defined by the program itself. American’s terms describe qualifying earning or redemption activity within the stated window as what prevents miles from expiring for most adult accounts. The exact list of qualifying actions lives in the program’s terms, not in this guide.

Because the definition of qualifying activity is program-specific, the reliable step is to read the current terms for the program that holds your balance. A redeeming flight, an earning flight, a partner transaction or an added purchase can each count differently, and assuming what counts is a guess this guide does not make. The program’s own page is the authority.

For the broader question of what a redemption can get you and how to search for award space, the how many points guide and the award flight search tools guide cover the value and discovery side, which is separate from keeping the balance alive.

Exceptions and edge cases

American’s reviewed exceptions make an activity-based rule specific. Members under age 21 are exempt from the 24-month expiration policy. Qualifying primary AAdvantage credit cardmembers are also exempt while the card account remains open. The current terms control the exact scope of both exceptions.

Do not expand those exceptions by analogy. Being an authorized user is not necessarily the same as being the qualifying primary cardmember, and turning 21 changes which rule applies. If an exception matters to your balance, read American’s live language and confirm the account status.

The same caution generalizes: program terms are revised, so an exception or a base rule that holds today can move. Confirm the current wording on the program’s own page before you rely on it, and note the date you checked. This guide’s figures are current to 11 August 2026.

How to protect a declining balance

Protecting a balance is simple where the rule is a rolling activity window: keep qualifying activity within the window. For a program like American’s, that means earning or redeeming in a way the terms count as qualifying, before the empty window would close. For a program like Delta’s, where miles do not expire, there may be less urgency, but account standing still matters.

The honest advice is not to spend miles just because you are nervous. If your program does not expire the balance, there is no cliff to race. If your program does, then the question is whether your recent qualifying activity actually resets the window. Confirm the program’s definition of qualifying activity rather than assuming any action works.

A before-you-assume checklist

1. Identify the program that holds the balance you care about; the rule is program-specific.
2. Read Delta’s page if the balance is SkyMiles: it states SkyMiles do not expire as of 11 August 2026.
3. Read American’s terms for AAdvantage: qualifying activity every 24 months, with stated exceptions for members under 21 and qualifying primary cardmembers.
4. Know Southwest’s rule: Rapid Rewards points do not expire, but closing the account forfeits them.
5. Verify United on its current rules page rather than assuming a result from this dated audit.
6. Separate miles from tickets and credits. An award ticket’s rules and a flight or travel credit’s expiry are not your miles expiration.
7. Recheck the program’s page before you rely on a balance, because program rules are revised by each airline.

Do airline miles expire? Only for the program that says they do, which is why the honest answer keeps Delta and American apart. Delta states SkyMiles do not expire, while American requires qualifying earning or redemption activity every 24 months for most adult accounts, with exceptions. And miles are not an award ticket and not a flight or travel credit, so track all three separately. Southwest also states that its points do not expire, while this dated audit leaves United for direct verification. Recheck the program’s rule when it matters.