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$38+ Cheap flights from Seattle to Denver (SEA - DEN)

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 3/13. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — DEN
Jan 9 — Jan 161
Fri 1/9
Fri 1/16
1 adult, Economy
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Find cheap flights from Seattle to Denver 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

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3. Compare prices and book

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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Denver Intl are usually found in January or September, booked 69 days in advance, depart on a Friday or Saturday and return on a Friday

Cheap flight deals from Seattle to Denver

Cheapest flights from Seattle to Denver
Explore the most affordable flight options available from Seattle to Denver. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 10, 2025.

This Expedia deal was found by Cheapflights users on 12/9. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/311:25 pmSEA - DEN
Nonstop2h 53mMultiple Airlines
Wed 1/77:00 amDEN - SEA
Nonstop3h 11mMultiple Airlines
Deal found 12/9$92
This Expedia deal was found by Cheapflights users on 12/10. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/311:25 pmSEA - DEN
Nonstop2h 53mMultiple Airlines
Mon 1/56:02 amDEN - SEA
Nonstop3h 08mMultiple Airlines
Deal found 12/10$122
This Frontier deal was found by Cheapflights users on 12/10. 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.
Wed 12/311:25 pmSEA - DEN
Nonstop2h 53mFrontier
Mon 1/56:35 amDEN - SEA
1 stop8h 19mFrontier
Deal found 12/10$125
This Kiwi.com deal was found by Cheapflights users on 12/9. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/311:25 pmSEA - DEN
Nonstop2h 53mFrontier
Wed 1/71:01 pmDEN - SEA
2 stops21h 03mFrontier
Deal found 12/9$133
This United Airlines deal was found by Cheapflights users on 12/9. 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 12/315:02 amSEA - DEN
Nonstop2h 49mUnited Airlines
Wed 1/77:45 amDEN - SEA
Nonstop3h 10mUnited Airlines
Deal found 12/9$147
This Kiwi.com deal was found by Cheapflights users on 12/8. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/302:54 pmSEA - DEN
Nonstop2h 49mMultiple Airlines
Tue 1/612:12 pmDEN - SEA
Nonstop3h 06mMultiple Airlines
Deal found 12/8$152
This Frontier deal was found by Cheapflights users on 12/9. 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.
Wed 12/311:25 pmSEA - DEN
Nonstop2h 53mFrontier
Fri 1/26:35 amDEN - SEA
1 stop8h 19mFrontier
Deal found 12/9$159

Find flight deals from Seattle to Denver

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Denver (DEN). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated December 10, 2025.

Most accurate provider

Mytrip
3 stars

Most trusted provider

Mytrip
3 stars

Round-trip from

$72
(Frontier)

One-way from

$38
(Priceline)

Popular in

December

Cheapest in

January

Average price

$244

Good round-trip deal

$207 or less

Good one-way deal

$110 or less
Provider with most accurate pricing for Seattle/Tacoma Intl-Denver Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Denver Intl flights.
Search Deals
From Seattle/Tacoma Intl to Denver Intl
Search Deals
One-way flight from Seattle/Tacoma Intl to Denver Intl
Search Deals
High demand for flights, 0% potential price rise
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 December 2025
Search Deals
Price to beat on a round-trip flight from Seattle/Tacoma Intl to Denver Intl.
Search Deals
Price to beat on a one-way flight from Seattle/Tacoma Intl to Denver Intl.
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Denver 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 December 10, 2025.
Use the filters below to find and compare flights from Seattle to Denver that are best for you.

Fly from

Seattle

Fly to

Denver

Route

Depart

Return

Price

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Wed 1/7

12:25 pm-4:11 pm

Nonstop2h 46m

Denver Intl

Wed 1/14

7:45 am-9:55 am

Nonstop3h 10m

$97

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Wed 2/25

1:40 pm-5:27 pm

Nonstop2h 47m

Denver Intl

Mon 3/2

6:40 am-8:51 am

Nonstop3h 11m

$97

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Fri 1/9

5:25 am-11:54 am

1 stop5h 29m

Denver Intl

Mon 1/12

6:29 am-8:40 am

Nonstop3h 11m

$107

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Sat 2/21

1:38 pm-9:06 pm

1 stop6h 28m

Denver Intl

Thu 3/26

6:30 am-8:38 am

Nonstop3h 08m

$107

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Sun 2/1

7:40 pm-11:25 pm

Nonstop2h 45m

Denver Intl

Wed 2/4

6:23 pm-12:09 am

1 stop6h 46m

$107

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Mon 1/12

1:38 pm-7:56 pm

1 stop5h 18m

Denver Intl

Fri 1/16

6:29 am-8:40 am

Nonstop3h 11m

$107

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Tue 2/10

7:40 pm-11:25 pm

Nonstop2h 45m

Denver Intl

Tue 2/24

12:50 pm-4:48 pm

1 stop4h 58m

$107

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Wed 2/25

1:40 pm-5:27 pm

Nonstop2h 47m

Denver Intl

Thu 2/26

5:30 am-9:45 am

1 stop5h 15m

$107

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Tue 2/24

7:40 pm-11:25 pm

Nonstop2h 45m

Denver Intl

Wed 2/25

6:50 pm-9:08 pm

Nonstop3h 18m

$117

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Thu 1/8

5:25 am-11:54 am

1 stop5h 29m

Denver Intl

Sun 1/11

6:23 pm-11:22 pm

1 stop5h 59m

$117

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/9

Showing 1-10 of 22 results
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Compare providers for flights from Seattle to Denver

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Seattle to Denver in December.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
CheapTicketsDealPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*2 stars
PricelinePrice Accuracy1 starTrust Score*3 stars
CheapfaremartPrice Accuracy-Trust Score*1 star
JustAirTicketPrice Accuracy-Trust Score*1 star
MytripPrice Accuracy3 starsTrust Score*3 stars
GotogatePrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Seattle-Denver flights, users find the pricing of Mytrip to be most consistent on Cheapflights vs. Mytrip Users can find the same prices on Seattle-Denver flight deals on Cheapflights vs. Mytrip >95% of the time. Price accuracy is based on data collected from Seattle-Denver flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-Denver flights, Cheapflights users trust Mytrip the most. Mytrip has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Seattle-Denver flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Seattle to Denver

Have a flexible travel schedule? Discover the best time to fly to Denver from Seattle 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 Seattle to Denver

How far ahead should I book a flight from Seattle to Denver?

Use this chart to determine the optimal time to book a round-trip flight from Seattle to Denver. Price data was last updated on December 5, 2025.

To ensure you get the cheapest price possible for a flight from Seattle to Denver, you should look to book at least 69 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

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

Currently, January is the cheapest month in which you can book a flight from Seattle to Denver (average of $49). Flying from Seattle to Denver in July is currently the most expensive (average of $100). 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 SEA to DEN?

Find hourly flight availability from Seattle to Denver. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 10, 2025.

A simple way to save on the total cost of your ticket is to fly from Seattle to Denver at noon. If you’re flexible enough to do this you can expect to save up to 28% on your trip compared to booking a flight in the morning.

What is the cheapest day to fly from Seattle to Denver?

Use this chart to determine the cheapest time to fly round-trip from Seattle to Denver. Price data was last updated on December 6, 2025.

Travelers seeking maximum savings on their Seattle to Denver flight should consider departing on Thursday at noon when fares are most often at their lowest. Monday mornings flights should be avoided if possible as fares are typically the most expensive at this time.

The best insider tips for Seattle to Denver flights

AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Seattle to Denver trip
Airlines
Frontier

Frontier's UpFront Plus guarantees an empty middle seat for added comfort.


Early check-in with Frontier helps secure your place on overbooked flights.

Read more about FrontierBy Marisa Garcia
Alaska Airlines

Saver Fare allows a carry-on but restricts seat selection and changes.


Alaska's Wi-Fi is a flat fee, ideal for business travelers needing connectivity.

Read more about Alaska AirlinesBy Robert Schrader
United Airlines

United's Economy Plus offers extra legroom and priority boarding for MileagePlus members.


Prepay for checked bags on United to save money on fees.

Read more about United AirlinesBy Harriet Baskas
Airports
SEA

Use SEA Spot Saver for free security screening appointments. Sign up online a few days before your flight to reduce wait times.

Read more about SEABy Brandon Schultz
DEN

Take the A Line train from DEN to Union Station for a quick, cost-effective ride into downtown Denver.

Read more about DENBy Emily Zemler
Our travel experts
Marisa Garcia

Marisa Garcia

Expert on Frontier

Marisa Garcia

Marisa Garcia

Marisa knows planes inside and out, spending 16 years working on aircraft in hangars at airports around the world. She is an aviation industry expert, specialized in airline interiors and regulations. Ten years ago, she pivoted to journalism. She shares her insights in leading aviation, travel, and business publications and on her site FlightChic.

Read more
Robert Schrader

Robert Schrader

Expert on Alaska Airlines

Robert Schrader

Robert Schrader

One of the web's original travel bloggers, Robert launched his first site Leave Your Daily Hell in 2009. Since then, he's expanded into destination niche sites (one each for Japan, Thailand and Taiwan), in addition to having written for the inflight magazines of Singapore Airlines and Korean Air. Overall, he's visited nearly 100 countries, and flies business as often as possible.

Read more
Harriet Baskas

Harriet Baskas

Expert on United Airlines

Harriet Baskas

Harriet Baskas

Harriet is an award-winning journalist who is happiest in an airport or an unusual museum. Her stories about airports, air travel, and the business of travel have appeared on NBC News, CNBC, USA TODAY, The Points Guy and other outlets. She is the creator of the StuckatTheAirport.com blog and the author of nine books. When not out on the road or exploring the latest airport amenities, she’s home in Seattle getting ready for the next adventure.

Read more
Emily Zemler

Emily Zemler

Expert on DEN

Emily Zemler

Emily Zemler

Emily is a freelance writer and book author based in London covering entertainment and travel. Her work has appeared in Los Angeles Times, Observer, and Conde Nast Traveler She has ventured to more than 40 countries and all seven continents, always in search of a great art museum. She has written extensively about hotels, luxury travel, and aviation.

Read more
Brandon Schultz

Brandon Schultz

Expert on SEA

Brandon Schultz

Brandon Schultz

Brandon Schultz is an award-winning food and travel writer based in New York City. His work has appeared in Forbes, AAA, Thrillist, Travel + Leisure, and The Daily Meal, among many others, and he is the author of 6 books, including 3 cookbooks.

Read more

Reviews of airlines servicing Denver

Get insights into the airlines that provide service to Denver. 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 Denver. Reviews last updated December 10, 2025.
Read reviews from past customers who have flown Alaska Airlines, Southwest, and Delta from Seattle to Denver. 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
11,427 reviews

Overall

8.0

Crew

8.5

Boarding

8.1

Food

7.1

Entertainment

7.0

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Alaska Airlines
8.0
Very good
11,427 reviews
Alaska Airlines
8.0
Very good
11,427 reviews

Overall

8.0

Crew

8.5

Boarding

8.1

Food

7.1

Entertainment

7.0

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Southwest
7.9
Good
4,252 reviews
Alaska Airlines
8.0
Very good
11,427 reviews

Overall

8.0

Crew

8.5

Boarding

8.1

Food

7.1

Entertainment

7.0

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Delta
7.9
Good
8,009 reviews
Alaska Airlines
8.0
Very good
11,427 reviews

Overall

8.0

Crew

8.5

Boarding

8.1

Food

7.1

Entertainment

7.0

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
United Airlines
7.4
Good
9,095 reviews
Alaska Airlines
8.0
Very good
11,427 reviews

Overall

8.0

Crew

8.5

Boarding

8.1

Food

7.1

Entertainment

7.0

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.
Frontier
5.8
Fair
3,084 reviews
Alaska Airlines
8.0
Very good
11,427 reviews

Overall

8.0

Crew

8.5

Boarding

8.1

Food

7.1

Entertainment

7.0

Comfort

7.8

Reviews

1 / 20
8.0
Excellent

Anonymous,Sep 2025

SEA - MKE

The crew were excellent, flight good, but the actual space for a person to occupy for 4 hours seems to get smaller and smaller 🤣. I am not overweight, and average height….very uncomfortable,, especially when I couldn’t recliner the seat at all, and the pocket in front doesn’t accommodate a water bottle.

Related info for your journey

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

  • What airports do I use to fly from Seattle to Denver?

    If you wish to fly to Denver from Seattle, then you need to book flights from Seattle/Tacoma Intl to Denver Intl. There are 24 flights from Seattle/Tacoma Intl (SEA) to Denver Intl (DEN) per day to choose from. Flights to Denver from Seattle/Tacoma Intl are available from 6 different airlines, which means you should have some options if you want to compare airfare deals. 2h 38m is how long a nonstop flight from Seattle to Denver Intl typically takes.

  • How popular is this Seattle to Denver flight route?

    Within the past month, 281 users have taken a look at flights from Seattle/Tacoma Intl to Denver Intl.

  • How long is the flight from Seattle to Denver?

    There are many flights that can get you from Seattle to Denver in 2h 46m. Fly via United Airlines or Delta to get the fastest option. The distance between Seattle and Denver is about 1022 mi. Most flights are nonstop.

  • What are the cheapest airlines flying from Seattle to Denver round-trip?

    Currently priced at $56, Frontier will fly you from Seattle to Denver and back. In addition to Frontier, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Hawaiian Airlines and Delta - these airlines can fly you to your destination from $78 and $98, respectively. These flights start at 74% lower than the current average price 3 months from now.

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

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $33. Users have also found prices from $73 and $78 on Delta and Alaska Airlines, respectively.

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

    No one likes to see their flight delayed. When booking a flight from Seattle to Denver consider choosing United Airlines (93%), Copa Airlines (91%) or Icelandair (91%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Seattle to Denver?

    Looking at all options, your cheapest flight can be booked for $53. While the most popular route (Seattle/Tacoma Intl - Denver Intl) can be booked for $74 on average, our data indicates $786 when flying from Seattle to Denver.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Seattle to Denver 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 Seattle to Denver?

    Currently, January is the cheapest month in which you can book a flight from Seattle to Denver (average of $49). Flying from Seattle to Denver in July is currently the most expensive (average of $100). 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 Denver?

Book flights to Denver if you plan to visit one of these locations
Black Hawk
Thornton
Westminster
Broomfield
Lakewood
Golden
Winter Park
Greeley
Lone Tree
Cripple Creek
Silverthorne
Central City
Frisco
Wheat Ridge
Manitou Springs
Fort Morgan
Brighton
Longmont
Idaho Springs
Parker

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Top 6 airlines flying from Seattle to Denver

Discover the top 6 airlines that operate flights from Seattle to Denver. 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 December 10, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$64Average$166FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$87Average$233FlexibilityNo cancel feeOn-time85%
DeltaCheapest$115Average$247FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$118Average$257FlexibilityNo cancel feeOn-time63%
Alaska AirlinesCheapest$149Average$298FlexibilityNo cancel feeOn-time75%
United AirlinesCheapest$149Average$298FlexibilityNo cancel feeOn-time69%

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