Yes they can, but don't worry - they don't have to.
As long as you earn any miles within the previous three months, your miles won't expire. If you don't meet that requirement though, any miles older than three months will expire.
Another way to earn miles and keep them from expiring is to get our Spirit World Mastercard® and make at least one purchase per month*.
Residents of Costa Rica, Dominican Republic, El Salvador, Guatemala, Honduras, Nicaragua and Panama can apply for the Spirit Promerica Mastercard® here.
You can also earn more miles by flying on us or using one of our many partners. You can even buy more miles for as little as $27 to top off your account for an award booking or to restart the clock on your miles balance.
*For information about rates, fees, other costs and benefits associated with the use of this credit card, or to apply, click on the link above and refer to the disclosures accompanying the online credit application. This credit card program is issued and administered by Bank of America, N.A.