United Flight 604 Deals & Information (2025/2026)

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United Flight 604 Route Deals From $162

The cheapest prices found with in the last 7 days for return flights were $317 and $162 for one-way flights to Denver Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Wed, Sep 17 - Wed, Sep 24
RSW
Southwest Florida Intl.
DEN
Denver Intl.
$317 Roundtrip, found 1 day ago
$317
Roundtrip
found 1 day ago
Select United flight, departing Wed, Sep 17 from Southwest Florida Intl. to Denver Intl., returning Wed, Sep 24, priced at $317 found 1 day ago

Frequently asked questions

What route does flight number UA604 take?
UA604 serves multiple routes, but the most common is between PHX and Denver Intl. Airport (DEN). If on a direct flight, you'll touch down in approximately 1 hour and 53 minutes. Multi-stop flights can also use the same number, as can flights on other routes.
How often is UA604 on time?
If you're flying with United Airlines on flight number UA604 from Phoenix Sky Harbor Intl. Airport to Denver, CO Airport (DEN-Denver Intl.), your trip runs according to schedule 92% of the time --- when you're running on a tight schedule, it's a relief knowing that your airline does too. In the rare event of an unexpected delay, the average wait is only 22 minutes. This trip has a 3.9-star rating.
What terminal does UA604 fly out of?
You'll most likely board the plane from Terminal 3 if you're setting off from Sky Harbor Intl. Airport (PHX). UA604 serves several different routes, but the direct flight between PHX and DEN is the most popular one.
What kind of plane is on flight number UA604?
You're likely to be cruising aboard the Airbus A320 if you've reserved a ticket on flight UA604 from PHX to Denver, CO Airport (DEN-Denver Intl.). This is the most commonly used aircraft model on this busy 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 UA604 flight with Travelocity, please visit our Customer Service Portal.