HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Seattle

$78+ Cheap flights from Colorado to Seattle (SEA)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 7/16. Fares are subject to change and may not be available on all flights or dates of travel.
DEN — SEA
Jul 7 — Jul 141
Mon 7/7
Mon 7/14
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Colorado to Seattle with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheap flight deals from Colorado to Seattle

Keep the following information in mind while searching for Colorado to Seattle flight deals. Data was last updated July 2, 2025.

Round-trip from

$129
(Frontier)

One-way from

$78
(Kiwi.com)

Popular in

May

Cheapest in

October

Average price

$233

Good round-trip deal

$216 or less

Good one-way deal

$141 or less
From Colorado to Seattle/Tacoma Intl
Search Deals
One-way flight from Colorado to Seattle/Tacoma Intl
Search Deals
Highest demand for flights based on searches. 11% potential increase in price ($25 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2025
Search Deals
Price to beat on a round-trip flight from Colorado to Seattle/Tacoma Intl.
Search Deals
Price to beat on a one-way flight from Colorado to Seattle/Tacoma Intl.
Search Deals

Find flight deals from Colorado to Seattle

Cheapest flights from Colorado to Seattle
Explore the most affordable flight options available from Colorado to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 2, 2025.

This Frontier deal was found by Cheapflights users on 7/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/3110:29 pmDEN - SEA
Nonstop3h 05mFrontier
Sat 8/96:25 amSEA - DEN
Nonstop2h 49mFrontier
Deal found 7/2$129
This Delta deal was found by Cheapflights users on 6/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/46:50 pmGJT - SEA
1 stop4h 24mDelta
Tue 9/95:30 amSEA - GJT
1 stop4h 00mDelta
Deal found 6/30$211
This Delta deal was found by Cheapflights users on 6/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/275:55 pmCOS - SEA
1 stop5h 25mDelta
Wed 9/311:55 pmSEA - COS
1 stop9h 21mDelta
Deal found 6/30$217
This Southwest deal was found by Cheapflights users on 6/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/76:55 pmCOS - SEA
1 stop6h 20mSouthwest
Tue 8/1210:45 pmSEA - COS
2 stops13h 55mSouthwest
Deal found 6/30$228
This United Airlines deal was found by Cheapflights users on 7/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/251:43 pmMTJ - SEA
2 stops9h 32mUnited Airlines
Wed 9/35:02 amSEA - MTJ
1 stop6h 45mUnited Airlines
Deal found 7/2$242
This United Airlines deal was found by Cheapflights users on 7/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/175:55 pmGJT - SEA
1 stop6h 04mUnited Airlines
Tue 7/226:45 amSEA - GJT
2 stops9h 11mUnited Airlines
Deal found 7/1$244
This American Airlines deal was found by Cheapflights users on 6/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/116:27 amCOS - SEA
1 stop9h 24mAmerican Airlines
Thu 8/2112:58 amSEA - COS
1 stop8h 04mAmerican Airlines
Deal found 6/30$287
This United Airlines deal was found by Cheapflights users on 7/2. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/101:25 pmHDN - SEA
1 stop5h 26mUnited Airlines
Wed 9/175:02 amSEA - HDN
1 stop6h 19mUnited Airlines
Deal found 7/2$289
This American Airlines deal was found by Cheapflights users on 6/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/97:15 amDRO - SEA
1 stop8h 19mAmerican Airlines
Tue 9/1610:09 amSEA - DRO
1 stop8h 50mAmerican Airlines
Deal found 6/30$298
This American Airlines deal was found by Cheapflights users on 6/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/294:31 pmGJT - SEA
1 stop9h 12mAmerican Airlines
Thu 8/73:15 pmSEA - GJT
1 stop8h 06mAmerican Airlines
Deal found 6/30$299
This United Airlines deal was found by Cheapflights users on 6/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/56:35 pmCOS - SEA
1 stop5h 24mUnited Airlines
Sat 8/96:45 amSEA - COS
2 stops12h 55mUnited Airlines
Deal found 6/30$302
This Alaska Airlines deal was found by Cheapflights users on 6/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/2912:14 pmGJT - SEA
1 stop7h 38mAlaska Airlines
Tue 8/511:25 amSEA - GJT
2 stops11h 52mAlaska Airlines
Deal found 6/30$304

Cheapflights Fare Finder

Customize your flight search to find flights from Colorado to Seattle that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 2, 2025.
Use the filters below to find and compare flights from Colorado to Seattle that are best for you.

Fly from

Colorado

Fly to

Seattle

Route

Depart

Return

Price

DenverSeattle

DEN - SEA

DENSEA

Denver Intl

Thu 7/31

10:29 pm-12:34 am

Nonstop3h 05m

Seattle/Tacoma Intl

Sat 8/9

6:25 am-10:14 am

Nonstop2h 49m

$129

Grand JunctionSeattle

GJT - SEA

GJTSEA

Grand Junction Regnl

Thu 9/4

6:50 pm-10:14 pm

1 stop4h 24m

Seattle/Tacoma Intl

Tue 9/9

5:30 am-10:30 am

1 stop4h 00m

$211

Colorado SpringsSeattle

COS - SEA

COSSEA

Colorado Springs

Wed 8/27

5:55 pm-10:20 pm

1 stop5h 25m

Seattle/Tacoma Intl

Sat 8/30

11:55 pm-10:16 am

1 stop9h 21m

$217

Colorado SpringsSeattle

COS - SEA

COSSEA

Colorado Springs

Thu 8/7

6:55 pm-12:15 am

1 stop6h 20m

Seattle/Tacoma Intl

Tue 8/12

10:45 pm-1:40 pm

2 stops13h 55m

$228

MontroseSeattle

MTJ - SEA

MTJSEA

Montrose County

Mon 8/25

1:43 pm-10:15 pm

2 stops9h 32m

Seattle/Tacoma Intl

Wed 9/3

5:02 am-12:47 pm

1 stop6h 45m

$242

Grand JunctionSeattle

GJT - SEA

GJTSEA

Grand Junction Regnl

Thu 7/17

5:55 pm-10:59 pm

1 stop6h 04m

Seattle/Tacoma Intl

Tue 7/22

6:45 am-4:56 pm

2 stops9h 11m

$244

Colorado SpringsSeattle

COS - SEA

COSSEA

Colorado Springs

Mon 8/11

6:27 am-2:51 pm

1 stop9h 24m

Seattle/Tacoma Intl

Thu 8/21

12:58 am-10:02 am

1 stop8h 04m

$287

HaydenSeattle

HDN - SEA

HDNSEA

Hayden Yampa Valley

Wed 9/10

1:25 pm-5:51 pm

1 stop5h 26m

Seattle/Tacoma Intl

Wed 9/17

5:02 am-12:21 pm

1 stop6h 19m

$289

DurangoSeattle

DRO - SEA

DROSEA

Durango La Plata County

Tue 9/9

7:15 am-2:34 pm

1 stop8h 19m

Seattle/Tacoma Intl

Tue 9/16

10:09 am-7:59 pm

1 stop8h 50m

$298

Grand JunctionSeattle

GJT - SEA

GJTSEA

Grand Junction Regnl

Tue 7/29

4:31 pm-12:43 am

1 stop9h 12m

Seattle/Tacoma Intl

Thu 8/7

3:15 pm-12:21 am

1 stop8h 06m

$299

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/2

Showing 1-10 of 47 results
1
2
3
...
5

Best time to book a flight from Colorado to Seattle

Have a flexible travel schedule? Discover the best time to fly to Seattle from Colorado with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from Colorado to Seattle

What is the cheapest month to book a flight from Colorado to Seattle?

Currently, January is the cheapest month in which you can book a flight from Colorado to Seattle (average of $238). Flying from Colorado to Seattle in July is currently the most expensive (average of $390). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from CO to SEA?

Find hourly flight availability from Colorado to Seattle. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 2, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Colorado to Seattle as you normally would.

Weekly flight availability from Colorado to Seattle

Explore weekly flight availability from Colorado to Seattle. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated July 2, 2025.

The most flights from USCO to SEA are scheduled on a Monday (59 on average). You will have fewer flight options on Friday, which is when the least amount of flights are scheduled (22 on average).

How much does it cost to fly round-trip from Colorado to Seattle?

Reviews of airlines servicing Seattle

Get insights into the airlines that provide service to Seattle. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Seattle. Reviews last updated July 2, 2025.
See what other customers who have flown with Alaska Airlines, Southwest, and Delta from Colorado to Seattle have to say. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Food

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Food

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Southwest
8.0
Very good
4,272 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Food

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Delta
8.0
Very good
7,983 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Food

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Hawaiian Airlines
7.8
Good
2,540 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Food

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
United Airlines
7.4
Good
8,861 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Food

7.1

Boarding

8.1

Overall

8.0

Crew

8.5

Comfort

7.8

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

Related info for your journey

Find useful and relevant information for your journey from Colorado to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Seattle from Colorado?

    Seattle/Tacoma Intl (SEA) is the airport you will fly into if you book a flight from Colorado to Seattle. It is only a 11.4 mi journey from Seattle/Tacoma Intl (SEA) to Seattle’s city center.

  • How popular is this Colorado to Seattle flight route?

    This flight path from Colorado to Seattle/Tacoma Intl was viewed by 205 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • What are the cheapest airlines to fly from Colorado to Seattle one-way?

    To fly one-way, consider booking your trip with Frontier, which is currently one of the cheapest options available, starting at $78. Delta flights start at $79 while deals on Alaska Airlines start at $87 one-way.

  • What are the most popular routes from Colorado to Seattle?

    Most travelers choose Denver Intl - Seattle/Tacoma Intl, Grand Junction Regnl - Seattle/Tacoma Intl or Colorado Springs - Seattle/Tacoma Intl when deciding on the best route from Colorado to Seattle.

  • What are the most reliable airlines from Colorado to Seattle?

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from Colorado to Seattle on time: Singapore Airlines (88%), ANA (82%), United Airlines (76%).

  • What are the cheapest flights from Colorado to Seattle?

    While on average a flight from Colorado to Seattle is generally $1,440, our data shows the cheapest flight currently is $88. When looking at the most popular route, (Denver Intl - Seattle/Tacoma Intl), you can expect to pay $98 for that flight.

  • Can I find deals for flights from Colorado to Seattle that include hotel bookings?

    Yes. In addition to deals on Colorado to Seattle flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Colorado to Seattle?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Colorado to Seattle.

  • Can I find deals for business class flights from Colorado to Seattle?

    Yes. Cheapflights offers flight deals from Colorado to Seattle by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Colorado to Seattle?

    Currently, January is the cheapest month in which you can book a flight from Colorado to Seattle (average of $238). Flying from Colorado to Seattle in July is currently the most expensive (average of $390). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near Colorado?

Book flights to Colorado if you plan to visit one of these locations
SeaTac
Tukwila
Tacoma
Lakewood
Ocean Shores
Lacey
Leavenworth
Lynnwood
Renton
Olympia
Shoreline
Puyallup
Cle Elum
Centralia
Kent
Federal Way
Chehalis
Kirkland
Aberdeen
Shelton

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Colorado to Seattle

See prices for flight routes from nearby airports that may be better suited for you.
Dallas/Fort Worth to Seattle flights
Los Angeles to Seattle flights
John F Kennedy Intl to Seattle flights
Ontario to Seattle flights
Newark to Seattle flights
San Francisco to Seattle flights
O'Hare Intl to Seattle flights
Hobby to Seattle flights
Los Angeles to Portland flights
Denver to Seattle flights
Dulles Intl to Seattle flights
Atlanta to Seattle flights
Santa Ana to Seattle flights
Reagan-National to Seattle flights
Philadelphia to Seattle flights
San Jose to Seattle flights
Boston to Seattle flights
Oakland to Seattle flights
LaGuardia to Seattle flights
Orlando to Seattle flights
Tampa to Seattle flights
Love Field to Seattle flights
George Bush Intcntl to Seattle flights
Dallas/Fort Worth to Portland flights
San Diego to Seattle flights
Baltimore to Seattle flights
Sky Harbor Intl to Seattle flights
Detroit to Seattle flights
Minneapolis to Seattle flights
Raleigh to Seattle flights
Los Angeles to Everett flights
San Francisco to Portland flights
Ontario to Portland flights
Burbank to Seattle flights
John F Kennedy Intl to Portland flights
O'Hare Intl to Portland flights
Las Vegas to Seattle flights
Midway to Seattle flights
Minneapolis to Portland flights
Newark to Portland flights
Burbank to Portland flights
Cleveland to Seattle flights
Honolulu to Seattle flights
Salt Lake City to Seattle flights
St. Louis to Seattle flights
Kansas City to Seattle flights
Austin to Seattle flights
San Francisco to Everett flights
Charlotte to Seattle flights
Columbus to Seattle flights

Top 7 airlines flying from Colorado to Seattle

Discover the top 7 airlines that operate flights from Colorado to Seattle. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated July 2, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$58Average$152FlexibilityNo cancel feeOn-time62%
DeltaCheapest$109Average$343FlexibilityNo cancel feeOn-timeN/A
Hawaiian AirlinesCheapest$115Average$259FlexibilityNo cancel feeOn-time85%
SouthwestCheapest$135Average$355FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$148Average$491FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$159Average$394FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$199Average$404FlexibilityNo cancel feeOn-time71%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.