H there,
When renting a car in Montana, you should be at least 21 years of age although some agencies set the age limit higher for certain vehicles.
I would recommend It's a Montana airport
car rental when looking to rent, and there are a handful of airports around the state that provide access to all the major car rental agencies.
If you're looking to go to
Glacier National Park for the chance to drive on the famed Going-to-the-Sun Road, for example, you can rent a car at the Glacier Park Airport, which is found in Kalispell.
Travadvice360