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$72+ 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 10/6. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — DEN
Oct 17 — Oct 241
Fri 10/17
Fri 10/24
1 adult, Economy
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Cheapflights Tip: The best prices from Seattle/Tacoma Intl to Denver Intl are usually found in October or November, booked 77 days in advance, depart on a Saturday or Friday and return on a Friday

Cheap 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 September 17, 2025.

Round-trip from

$96
(Frontier)

One-way from

$72
(Cheapflightsfares)

Popular in

December

Cheapest in

October

Average price

$189

Good round-trip deal

$175 or less

Good one-way deal

$135 or less
From Seattle/Tacoma Intl to Denver Intl
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One-way flight from Seattle/Tacoma Intl to Denver Intl
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High demand for flights, 0% potential price rise
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Cheapest flight prices on average. 2% potential price decrease ($5 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Price to beat on a round-trip flight from Seattle/Tacoma Intl to Denver Intl.
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Price to beat on a one-way flight from Seattle/Tacoma Intl to Denver Intl.
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Find 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 September 17, 2025.

This Trip.com deal was found by Cheapflights users on 9/17. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/118:43 pmSEA - DEN
Nonstop2h 52mFrontier
Mon 10/135:30 amDEN - SEA
Nonstop3h 03mFrontier
Deal found 9/17$95
This Frontier deal was found by Cheapflights users on 9/16. 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.
Fri 10/312:22 pmSEA - DEN
Nonstop2h 51mFrontier
Wed 11/510:00 amDEN - SEA
Nonstop3h 13mFrontier
Deal found 9/16$96
This Cheapflightsfares deal was found by Cheapflights users on 9/16. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/312:22 pmSEA - DEN
Nonstop2h 51mFrontier
Mon 11/310:50 amDEN - SEA
Nonstop3h 13mFrontier
Deal found 9/16$98
This Cheapflightsfares deal was found by Cheapflights users on 9/17. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/178:43 pmSEA - DEN
Nonstop2h 52mFrontier
Thu 10/239:58 amDEN - SEA
Nonstop3h 09mFrontier
Deal found 9/17$99
This Cheapflightsfares deal was found by Cheapflights users on 9/16. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/178:43 pmSEA - DEN
Nonstop2h 52mFrontier
Sun 10/195:30 amDEN - SEA
Nonstop3h 03mFrontier
Deal found 9/16$100
This Flightnetwork deal was found by Cheapflights users on 9/17. 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 Flightnetwork is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/108:43 pmSEA - DEN
Nonstop2h 52mFrontier
Sun 10/125:30 amDEN - SEA
Nonstop3h 03mFrontier
Deal found 9/17$101
This Mytrip deal was found by Cheapflights users on 9/16. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/228:43 pmSEA - DEN
Nonstop2h 52mFrontier
Mon 10/279:58 amDEN - SEA
Nonstop3h 09mFrontier
Deal found 9/16$102
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/56:12 amSEA - DEN
Nonstop2h 56mFrontier
Tue 10/79:58 amDEN - SEA
Nonstop3h 09mFrontier
Deal found 9/15$103
This Priceline deal was found by Cheapflights users on 9/17. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/108:43 pmSEA - DEN
Nonstop2h 52mFrontier
Tue 10/149:58 amDEN - SEA
Nonstop3h 09mFrontier
Deal found 9/17$104
This Cheapflightsfares deal was found by Cheapflights users on 9/17. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/247:00 amSEA - DEN
Nonstop2h 53mFrontier
Fri 10/245:30 amDEN - SEA
Nonstop3h 03mFrontier
Deal found 9/17$105
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/188:43 pmSEA - DEN
Nonstop2h 52mFrontier
Tue 10/219:58 amDEN - SEA
Nonstop3h 09mFrontier
Deal found 9/15$106
This Priceline deal was found by Cheapflights users on 9/15. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/1112:58 pmSEA - DEN
Nonstop2h 59mFrontier
Mon 11/1710:00 amDEN - SEA
Nonstop3h 13mFrontier
Deal found 9/15$107

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 September 17, 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

Fri 10/31

7:30 pm-11:14 pm

Nonstop2h 44m

Denver Intl

Sun 11/2

5:25 am-7:31 am

Nonstop3h 06m

$133

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Wed 11/5

7:35 am-11:28 am

Nonstop2h 53m

Denver Intl

Wed 11/5

6:23 pm-11:59 pm

1 stop6h 36m

$143

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Sat 1/3

7:59 pm-11:47 pm

Nonstop2h 48m

Denver Intl

Sat 1/10

6:15 am-8:24 am

Nonstop3h 09m

$155

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Wed 12/3

7:35 pm-11:21 pm

Nonstop2h 46m

Denver Intl

Sat 12/6

7:45 pm-10:01 pm

Nonstop3h 16m

$157

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Sat 10/25

5:59 pm-9:46 pm

Nonstop2h 47m

Denver Intl

Tue 10/28

8:20 am-2:50 pm

1 stop7h 30m

$177

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Tue 3/3

7:40 pm-11:22 pm

Nonstop2h 42m

Denver Intl

Wed 3/4

6:15 am-8:24 am

Nonstop3h 09m

$177

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Thu 10/30

9:55 am-7:30 pm

2 stops8h 35m

Denver Intl

Sun 11/2

10:35 pm-12:35 am

Nonstop3h 00m

$178

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Wed 10/15

1:20 pm-9:20 pm

1 stop7h 00m

Denver Intl

Sun 10/19

10:40 pm-12:35 am

Nonstop2h 55m

$185

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Tue 3/3

9:55 am-6:33 pm

1 stop7h 38m

Denver Intl

Wed 3/4

7:00 am-9:00 am

Nonstop3h 00m

$187

SeattleDenver

SEA - DEN

SEADEN

Seattle/Tacoma Intl

Wed 10/15

1:20 pm-11:50 pm

2 stops9h 30m

Denver Intl

Wed 10/22

3:30 pm-10:55 pm

1 stop8h 25m

$192

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/16

Showing 1-10 of 21 results
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The best insider tips for Seattle to Denver flights

Snippets provided in this section are AI-generated based on a summarization of Cheapflights-commissioned articles. The articles are presented as-is, for general informational purposes only, and may not be up-to-date. The opinions contained in the articles are original to the author and reflect their authentic experience, which may vary significantly from the experience of others.
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

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 September 12, 2025.

To ensure you get the cheapest price possible for a flight from Seattle to Denver, you should look to book at least 77 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, October is the cheapest month in which you can book a flight from Seattle to Denver (average of $197). Flying from Seattle to Denver in March is currently the most expensive (average of $278). 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 September 17, 2025.

A simple way to save on the total cost of your ticket is to fly from Seattle to Denver in the evening. If you’re flexible enough to do this you can expect to save up to 29% 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 September 14, 2025.

Travelers seeking maximum savings on their Seattle to Denver flight should consider departing on Tuesday evenings 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.

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 September 17, 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
10,000 reviews

Comfort

7.8

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

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
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Comfort

7.8

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

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
8.0
Very good
4,242 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Comfort

7.8

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

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
8.0
Very good
7,961 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Comfort

7.8

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

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
8,926 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Comfort

7.8

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

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
3,173 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Comfort

7.8

Crew

8.5

Entertainment

7.1

Boarding

8.1

Food

7.1

Overall

8.0

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 35 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 35m 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, 306 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 44m. Fly via 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 $67, 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 $87 and $117, respectively. These flights start at 68% lower than the current average price 3 months from now.

  • 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 ANA (82%), China Airlines (82%) or United Airlines (79%) 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 $79. While the most popular route (Seattle/Tacoma Intl - Denver Intl) can be booked for $86 on average, our data indicates $655 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, October is the cheapest month in which you can book a flight from Seattle to Denver (average of $197). Flying from Seattle to Denver in March is currently the most expensive (average of $278). 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
Westminster
Golden
Winter Park
Lakewood
Broomfield
Greeley
Lone Tree
Cripple Creek
Thornton
Silverthorne
Manitou Springs
Fort Morgan
Glendale
Wheat Ridge
Brighton
Longmont
Idaho Springs
Parker
Sterling

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Alternative routes for Seattle to Denver

See prices for flight routes from nearby airports that may be better suited for you.
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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 September 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$67Average$161FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$87Average$232FlexibilityNo cancel feeOn-time85%
DeltaCheapest$117Average$250FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$127Average$252FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$149Average$310FlexibilityNo cancel feeOn-time69%
Alaska AirlinesCheapest$168Average$302FlexibilityNo cancel feeOn-time75%

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