$79 Cheap United flights Seattle (SEA) to Denver (DEN)

View $79 flight on Sat, Oct 18, 2025Opens in a new window

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$79 Cheap United flights Seattle (SEA) to Denver (DEN)

Prices were available within the past 7 days and start at $79 for one-way flights and $144 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Sat, Oct 18 - Wed, Oct 22
SEA
Seattle
DEN
Denver
$144 Roundtrip, just found
$144
Roundtrip
just found
Select United flight, departing Sat, Oct 18 from Seattle to Denver, returning Wed, Oct 22, priced at $144 just found
United
Sat, Oct 18 - Wed, Oct 22
SEA
Seattle
DEN
Denver
$157 Roundtrip, just found
$157
Roundtrip
just found
Select United flight, departing Sat, Oct 18 from Seattle to Denver, returning Wed, Oct 22, priced at $157 just found
United
Mon, Oct 27 - Sat, Nov 1
SEA
Seattle
DEN
Denver
$161 Roundtrip, found 6 hours ago
$161
Roundtrip
found 6 hours ago
Select United flight, departing Mon, Oct 27 from Seattle to Denver, returning Sat, Nov 1, priced at $161 found 6 hours ago
United
Wed, Nov 12 - Sat, Nov 15
SEA
Seattle
DEN
Denver
$169 Roundtrip, found 1 hour ago
$169
Roundtrip
found 1 hour ago
Select United flight, departing Wed, Nov 12 from Seattle to Denver, returning Sat, Nov 15, priced at $169 found 1 hour ago
Flights from Seattle (SEA) to Denver (DEN)
Origin airport
Seattle - Tacoma Intl.
Destination airport
Denver Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Hawaiian Airlines, Southwest Airlines, United
Popular airline
Alaska Airlines
Distance
1022 mi
Average flight time
3 hours 41 mins

Frequently asked questions

How much is a United Airlines flight from Seattle - Tacoma Intl. Airport (SEA) to Denver Intl. Airport (DEN)?
You'll discover cheap return United Airlines flights from $144 from SEA to DEN by filtering your results from "Price (lowest to highest)" on Expedia. Or look for options from $79 for a one-way trip.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.
What is the cheapest month to fly from SEA to DEN with United Airlines?
January is one of the least expensive months to jet off to Denver with United Airlines. You could also find great deals on return and one-way fares in November.
What is the cheapest time to book flights from Seattle - Tacoma Intl. Airport (SEA) to Denver Intl. Airport (DEN) with United Airlines?
Look for affordable United Airlines flights from Seattle - Tacoma Intl. Airport (SEA) to Denver Intl. Airport (DEN) one to three months before your day of departure. Travelers who book domestic flights 34 to 86 days in advance can save 25% compared to those who book just 6 to 12 days ahead. Regardless of fare class and itinerary, the ideal day to book a domestic flight is generally Sunday and the most expensive day is typically Monday. Passengers who book on a Sunday can save 6% on average compared to those who book their travel on a Monday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.
Does United Airlines fly nonstop from Seattle - Tacoma Intl. Airport (SEA) to Denver Intl. Airport (DEN)?
Yes, you can fly from Seattle - Tacoma Intl. Airport (SEA) to Denver Intl. Airport (DEN) on one of United Airlines's 33 weekly direct flights. Use Expedia's "Nonstop" and "Airline" filters to find the United Airlines flight that'll take you to DEN at your preferred time.
How long does it take to fly from SEA to DEN with United Airlines?
It takes approximately 2h 42m to fly nonstop from Seattle - Tacoma Intl. Airport (SEA) to Denver Intl. Airport (DEN) with United Airlines.
Which day of the week has the most United Airlines flights from Seattle - Tacoma Intl. Airport (SEA) to Denver Intl. Airport (DEN)?
If you're looking for flexibility, Thursday offers the most choice for United Airlines flights from Seattle - Tacoma Intl. Airport (SEA) to Denver Intl. Airport (DEN). Take your pick of 5 different departures.
What is the earliest United Airlines flight from SEA to DEN?
Setting off from SEA at 5:00AM UTC-8, the earliest United Airlines flight to DEN arrives at 8:43AM UTC-7. Traveling earlier in the day means you'll be less likely to encounter delays.* Not a morning person? The last United Airlines flight from SEA to DEN departs at 6:00PM UTC-8 and touches down at 9:44PM UTC-7.*Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports does United Airlines fly into in Denver?
United Airlines flights from Seattle - Tacoma Intl. Airport (SEA) to Denver land at Denver Intl. Airport (DEN). This is the main entry point to this city.
Why fly with United Airlines from SEA to DEN?
A rewarding loyalty program and the ability to collect points through United Mileage Plus are the start of the reasons to leave from SEA to DEN with United Airlines. Plus, by joining Expedia's free One Key™ program, you can earn OneKeyCash™* on top of any airline loyalty program earnings. You can put it toward your future trips.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
What type of plane does United Airlines fly from Seattle - Tacoma Intl. Airport (SEA) to Denver Intl. Airport (DEN)?
You'll likely be seated on a Boeing 737 MAX 9 or an Airbus A321neo when flying United Airlines from Seattle - Tacoma Intl. Airport (SEA) to Denver Intl. Airport (DEN). However, keep in mind that a different aircraft could be assigned to your route depending on operational reasons.
Can I change or cancel my United Airlines flight from Seattle - Tacoma Intl. Airport (SEA) to Denver Intl. Airport (DEN)?
Depending on the type of ticket you purchased, a fee is typically charged if you modify or cancel your flight more than 24 hours after confirmation. To secure tickets with more flexibility, select our "No cancel fee" or "Changes included" filter when you search for flights. For more details on canceling or modifying your reservation, head to "Trips," select your flight and click on "Manage Booking."

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