Everyone knows that you need a boarding pass and driver’s license to pass airport security. It’s always been this way, but next year, some travelers may also need a passport card.

Starting on Jan. 22, 2018, travelers from a handful of states may have to show an alternate ID to Transportation Security Administration (TSA) agents at the airport. This is because the REAL ID Act, which was passed by Congress in 2005, will go into effect.

Essentially, this act established minimum security standards for state-issued driver’s licenses (and ID cards), and prohibits the TSA from accepting cards that don’t meet the standards. Several states have requested extensions to become compliant, many of which expired on Oct. 10. New extensions may be granted, but for now, the grace period for states ends on Jan. 22.

View photos States that are compliant with the REAL ID Act. More

Currently, only 26 states are fully compliant, so residents of those areas can continue to use their state-issued driver’s license when passing through airport security. The remaining states, including New York, California, Illinois and Louisiana, are currently under review. This means that they may be granted an extension and given more time to become compliant. Or it could mean that residents of these states will have to use an alternative form of ID when flying in 2018.

Alternative forms of ID

The easiest back-up ID option is your passport. The problem, is that only 36% of Americans have a valid passport, according to the U.S. Department of State.

At $135, passports can be expensive and unnecessary, especially if you have no desire to travel internationally. In this case, a passport card may make the most sense. For starters, it’s cheaper. First-time adult applicants can get one for $55, and the cost is $40 for children. The card is valid for 10 years (5 years if you’re 16 or younger), after which a renewal will cost $30.

Another perk of a passport card that makes it better than a license is that it allows for some international travel. Cardholders can use the wallet-sized document to re-enter the U.S. at border-crossings or ports-of-entry from Canada, Mexico, the Caribbean and Bermuda.

The TSA has a full list of all identification that will be accepted, but some of the more popular alternatives include:

DHS trusted traveler cards (Global Entry, NEXUS, SENTRI, FAST)

U.S. military ID (active duty or retired military and their dependents, and DoD civilians)

Permanent resident card

Border crossing card

DHS-designated enhanced driver’s license

Time is of the essence

It’s unclear if any states will be granted an extension, so if your state isn’t currently compliant, it’s time to consider some other options. A passport can take four to six weeks to arrive, while a passport card can take up to three weeks. Applying now means shorter wait times, compared with next year when procrastinators will be looking for new IDs before their spring trips.

Even if your state does get an extension, it doesn’t hurt to just get it out of the way. Beginning Oct. 1, 2020, you can only use a REAL ID compliant driver’s license or another acceptable form of identification for domestic air travel.

Article was edited to clarify that passport cards can only be used at border-crossings or ports-of-entry.

Brittany is a reporter at Yahoo Finance.

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