United Flight 403 Deals & Information (2026/2027)

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Frequently asked questions

What route does flight number UA403 take?
UA403 is used on a number of routes. Most commonly, UA403 flies direct from DEN to Los Angeles, CA Airport (LAX-Los Angeles Intl.). If this is your route, you'll be airborne for approximately 2 hours and 24 minutes.
What kind of plane is on flight number UA403?
It's likely you'll be traveling aboard a Boeing 737 MAX 9 if you're booked on flight UA403 from DEN to LAX. This is the most commonly used type of aircraft on this particular route.
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 UA403 flight with Travelocity, please visit our Customer Service Portal.