United Flight 351 Deals & Information (2025/2026)

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Change your flight without a fee on select flights

Frequently asked questions

What route does flight number UA351 take?
You'll arrive into Denver, CO Airport (DEN-Denver Intl.) from IAD if you're traveling on flight number UA351. You'll be airborne for 3 hours and 59 minutes during this journey. It's also good to note that the flight conveniently operates non-stop.
What kind of plane is on flight number UA351?
Prepare to cruise the skies aboard a Boeing 737 MAX 9 if you're traveling on flight UA351. Almost all services from Dulles Intl. Airport to Denver, CO Airport (DEN-Denver Intl.) use this aircraft model.
If I am not able to travel due to COVID-19, can I change my flight to a later date?
For more info about changing your UA351 flight with Travelocity, please visit our Customer Service Portal.