Cheap Flights from Denver (DEN) to St. Marys (KSM)

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Frequently asked questions

Is it cheaper to buy a plane ticket from Denver Intl. Airport (DEN) to St. Marys Airport (KSM) last minute?
When it's time to book your flights, being prepared pays off. While it's possible to pick up a last-minute deal on a DIA airport to St. Marys Airport flight, tickets usually don't get cheaper as the departure date nears. Based on flight pricing and demand studies in 2022, we have found that the sweet spot to book a domestic flight is between 28 – 35 days in advance. For international trips it's three to four months.
What airports do you fly into for St. Mary's from Denver?
To journey from Denver to St. Mary's, you can arrive at St. Marys Airport (KSM), Pilot Station Airport (PQS) or Mountain Village Airport (MOU). Touch down at St. Marys Airport (KSM) and you'll be about 3 kilometers southwest of downtown St. Mary's. Whichever hub you decide on, Expedia will help you find an amazing flight deal.
Can I change the date of my flight from Denver Airport to St. Marys Airport?
It's a snap to make changes to your Denver Airport to St. Marys Airport journey yourself. Access your details via the Expedia Trips portal and choose "change flight." Look around for new flights and secure the one that better fits your plans. You'll see an estimate of your flight change cost, if applicable. Alternatively, use our Customer Service portal to chat to our Virtual Agent and quickly get answers to your questions.

Travel information

Origin airport
Denver Intl.
Destination airport
St. Marys
Distance
4542 km

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