Maine Among 9 States that May Require Passports for Flights
This new requirement might make air travel more complicated for some flyers. Beginning in the new year, residents of nine states might need a U.S. passport to board any flight, domestic or international, according to new TSA guidelines. The nine states possibly affected are Maine, Kentucky, Minnesota, Missouri, Montana, Oklahoma, Pennsylvania, South Carolina and Washington.
That said, Maine Gov. Paul LePage signed in April a law that will bring the state into compliance, according to maine.gov.
The state was able to receive a waiver that is valid through October 2017 and can be renewed annually as long as "the state can demonstrate compliance."
According to the state:
During this waiver period, Maine credentials (driver’s licenses and IDs) will be accepted as valid identification for federal purposes, such as entrance to federal facilities.
Maine expects to have a waiver by Jan. 22, 2018, the deadline for compliance, and will be working to enable the state to issue Real ID-compliant licenses during that time.
So by that time, Maine residents should still be able to use their driver's licenses, if there is a waiver, but a passport will definitely get you on a flight.