Flight
The Missoula airport is small and will be the most expensive and have a limited number of flights per day. However, it is the most efficient. MSO is a 10-15 minute drive to downtown Missoula and in terms of getting in and out, it will likely be the most seamless airport experience you've ever had.
Flight
Bozeman will have cheaper flight options but keep in mind that it is a 3 hour drive to Missoula. If you plan on making a trip out to Yellowstone while you're here, this will be your best option.
Flight
Another airport that may have cheaper flight options is Spokane. This will be about a 3 hour drive into Missoula. Also keep in mind that you will cross timezones on this drive so you will lose an hour traveling into Montana.
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