DEN - SEA

£81 Find Cheap Flights from Denver to Seattle

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Denver to Seattle departing on 30/9. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Seattle

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Denver to Seattle, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Denver to Seattle, as well as popular online travel agencies
Travellers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

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Everything you should know

Cheapest return fare
£146
Typical prices: £237-£117
Delta
Wed 2/9Tue 8/9
DEN - SEA • Direct
Cheapest direct flights
£146
Typical prices: £217-£117
Delta
Tue 11/8Tue 18/8
DEN - SEA • Direct
Advice from real travellers
AI-powered summary based on content written by KAYAK users. AI can make mistakes.
On Delta, a left-side window seat can offer views of Mt. Rainier near Seattle.
At Denver, arrive early; TSA lines vary, and gates can take 20–30 minutes to reach.
User tips
User tips
User tips
User tips
Top airlines
Cheapest • from £146 (return)
Best reviews • 5.6 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
Direct flights
You can fly direct with Alaska Airlines, Delta, and others. Average duration is 3h 00m
Direct flights
Direct flights
+1
+1
Direct flights
Direct flights
+1
Avoid delays
Most punctual • 87% on-time
Best time • Fewest delays
Insights
Insights
Insights
Insights
When to book
in advance
Our data shows that travellers who book at least 3 weeks in advance save around 35% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 37% price drop
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
Start a new search
KAYAK searches hundreds of sites at once to find you the best travel deals.
We hope you love your trip to Seattle!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Denver to Seattle (DEN-SEA)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights from Denver to Seattle that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent return flight deals from Denver to Seattle

Wed, 2 Sep - Tue, 8 Sep
Delta Logo
13:21 - 15:23
DEN
-
SEA
3h 02mdirect
Delta Logo
19:40 - 23:30
SEA
-
DEN
2h 50mdirect
£146Delta
Wed, 15 Jul - Tue, 21 Jul
Frontier Logo
09:13 - 11:20
DEN
-
SEA
3h 07mdirect
Frontier Logo
19:06 - 22:58
SEA
-
DEN
2h 52mdirect
£146Frontier
Wed, 15 Jul - Wed, 22 Jul
Frontier Logo
07:13 - 09:17
DEN
-
SEA
3h 04mdirect
Frontier Logo
19:06 - 22:58
SEA
-
DEN
2h 52mdirect
£158Frontier
Wed, 9 Sep - Sat, 12 Sep
Delta Logo
18:30 - 20:40
DEN
-
SEA
3h 10mdirect
Delta Logo
19:40 - 23:30
SEA
-
DEN
2h 50mdirect
£160Delta
Wed, 15 Jul - Wed, 22 Jul
Frontier Logo
07:25 - 17:51
DEN
-
SEA
11h 26m
1 stop
Frontier Logo
12:35 - 16:40
SEA
-
DEN
3h 05mdirect
£163Frontier
Fri, 3 Jul - Tue, 7 Jul
Frontier Logo
12:14 - 14:18
DEN
-
SEA
3h 04mdirect
Frontier Logo
19:06 - 22:58
SEA
-
DEN
2h 52mdirect
£166Frontier
Fri, 3 Jul - Tue, 7 Jul
Frontier Logo
08:44 - 18:57
DEN
-
SEA
11h 13m
1 stop
Frontier Logo
19:06 - 22:58
SEA
-
DEN
2h 52mdirect
£169Frontier
Thu, 3 Sep - Wed, 9 Sep
Delta Logo
06:20 - 08:19
DEN
-
SEA
2h 59mdirect
Delta Logo
19:40 - 23:30
SEA
-
DEN
2h 50mdirect
£172Delta
Wed, 12 Aug - Wed, 19 Aug
Southwest Logo
21:05 - 23:05
DEN
-
SEA
3h 00mdirect
Southwest Logo
12:55 - 16:35
SEA
-
DEN
2h 40mdirect
£175Southwest
Mon, 29 Jun - Mon, 29 Jun
Frontier Logo
07:45 - 09:48
DEN
-
SEA
3h 03mdirect
Frontier Logo
19:41 - 23:36
SEA
-
DEN
2h 55mdirect
£178Frontier
Booking Insights

KAYAK’s insights & trends for Denver to Seattle flights

Get data-powered insights and trends into flights from Denver to Seattle to help you find the cheapest flights, the best time to fly and much more.

How much is a return flight from Denver to Seattle?

This analysis is based on the cheapest return trip price found on KAYAK in the last 12 months by searching for a flight from Denver to Seattle departing in September.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Denver to Seattle, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from Denver to Seattle is January, where tickets cost £103 (return) on average. On the other hand, the most expensive months are June and July, where the average cost of round-trip tickets is £208 and £199 respectively.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Denver to Seattle, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from Denver to Seattle, you should book around 3 weeks before departure, which saves you about 35% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 4 weeks before departure.

Good to know - Cheap tickets from Denver to Seattle

Low seasonJanuary
Cheapest flight£81
Best time to beat the crowds (37% less expensive on average)
Most popular time to fly (28% more expensive on average)
Flight from Denver to Seattle

When to book flights from Denver to Seattle

Are your dates flexible? Find out the best times to travel from Denver to Seattle based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated return price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or returns with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

Flights from Denver to Seattle: the best tips from KAYAK users' own experiences

Insights shared by verified travellers who flew the route from Denver to Seattle 
Verified travelerFlew with Delta
DEN
-
SEA
Jun 2025
If you are on the left side of the plane you should spot Mt. Rainer on your way into Seattle.
Verified travelerFlew with Alaska Airlines
DEN
-
SEA
Oct 2024
Go early, it’s a big airport. There are two TSA screening areas, one might be more crowded than the other. From checking it to the gate give yourself at least 20-30 minutes to get there.

FAQs for booking flights from Denver to Seattle

  • What is the cheapest flight from Denver to Seattle?

    In the last 3 days, the lowest price for a flight from Denver to Seattle was £81 for a one-way ticket and £146 for a return.

  • Which airlines offer Wi-Fi service onboard planes from Denver to Seattle?

    Alaska Airlines, JetBlue, Delta, and Lufthansa offer inflight Wi-Fi service on the Denver to Seattle flight route.

  • Which aircraft models fly most regularly from Denver to Seattle?

    The Airbus A321neo is the aircraft model that flies most regularly on the Denver to Seattle flight route.

  • On which days can I fly direct from Denver to Seattle?

    There are direct flights from Denver to Seattle on a daily basis.

  • How does KAYAK find such low prices on flights from Denver to Seattle?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Denver to Seattle.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Denver to Seattle?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from Denver is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Denver to Seattle?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly to Seattle with an airline and back to Denver with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Denver to Seattle?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Seattle from Denver up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from Denver to Seattle

  • Looking for a cheap flight from Seattle to Denver? 25% of our users found flights on this route for £135 or less one-way.

Prefer to fly direct from Denver to Seattle?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Denver Intl to Seattle/Tacoma Intl.
Find which airlines fly direct from Denver Intl Airport to Seattle/Tacoma Intl Airport, which days they fly and book direct flights.

Direct departures

Denver Intl to Seattle/Tacoma Intl

Monday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Tuesday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Wednesday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Thursday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Friday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Saturday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Sunday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

See more direct flights

Direct returns

Seattle/Tacoma Intl to Denver Intl

Monday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Tuesday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Wednesday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Thursday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Friday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Saturday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

Sunday

Alaska Airlines,Delta,Frontier, +2 more

Alaska Airlines,Delta, +3 more

See more direct flights

Reviews of the top airline flying from Denver to Seattle

 
See real verified KAYAK customer reviews for airlines flying from Denver to Seattle. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Denver to Seattle? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
5.6
FrontierOverall score based on 2908 reviews
4.3Entertainment
5.4Comfort
4.5Food
5.9Boarding
6.5Crew
Airline reviews

There weren't enough employees at check in took awhile to get bags checked. There wasn't a wheel chair for me, I was sent to someone who turns out to work for a different airline, if My flight hadn't been delayed I probably would have missed my flight as it was, by the time I arrived at my gate, they started boarding in about 15 minutes. I don't know who took me to my gate, definitely was not the normal people who take passengers to the gate. I'm guessing she may have been in a management position. I wish I knew her name, she went beyond to help me. With that said everyone was kind, and were doing the best they could. So, I choose to say it was an Adventure, stressful start, but good. In the end went well. The situation was not only difficult for passengers but the employee's.

6.0 GoodLinda, May 2026
AUS - DEN
Read more Frontier reviews

There weren't enough employees at check in took awhile to get bags checked. There wasn't a wheel chair for me, I was sent to someone who turns out to work for a different airline, if My flight hadn't been delayed I probably would have missed my flight as it was, by the time I arrived at my gate, they started boarding in about 15 minutes. I don't know who took me to my gate, definitely was not the normal people who take passengers to the gate. I'm guessing she may have been in a management position. I wish I knew her name, she went beyond to help me. With that said everyone was kind, and were doing the best they could. So, I choose to say it was an Adventure, stressful start, but good. In the end went well. The situation was not only difficult for passengers but the employee's.

The staff at the check in counter was so rude. Made you feel Incompetent

Frontier scheduled a 40 minute connection in DEN. What they failed to mention was that they “close the doors” 20 mins prior to departure, which means you only have 20 mins. Not enough time. Possibly against DOT regulations. Filing complaint.

Flight was scheduled at 9:40pm. Got delayed to 10 am, the next day. crazy

The bag check, flight check-in, and onboard experience convinced my wife and me that we will actively go out of our way to avoid flying Frontier Airlines in the future. At bag check, we were informed that check-in could only be completed via the Frontier mobile app. Unfortunately, the app was extremely frustrating—sending us through repetitive, confusing loops that repeatedly forced us to decline add-on services with nearly every click. While most airline apps upsell, this one felt intentionally exhausting. As the process dragged on, we became genuinely concerned that my phone battery would die before check-in could be completed. We approached the bag check staff—who were standing together talking—and explained both our frustration and our predicament. They laughed. Later, my wife described the interaction as “gaslighting,” which felt accurate. We were then informed it would cost $25 per person simply to have our boarding passes printed. From that point forward, the tone of the experience was consistently hostile. The bag check employees were condescending and combative, behaving more like bullies than customer service staff. Unfortunately, that same attitude continued onboard. One flight attendant argued with me when I attempted to stow my backpack in the overhead bin. I explained that we had each paid $75 to check our bags specifically so we would not need to use carry-on space and could have adequate legroom. She demanded to see my ticket, pointed out that it said “no carry-on”—which I acknowledged—and I reiterated that this was precisely why we paid to check our bags. Her response was, “I don’t make the rules.” She then walked away, but not before asking if I “truly wanted to fly back to Chicago today?”—an unnecessary and unmistakable threat. It is also worth noting that despite booking our tickets together in the same transaction, we were not seated together. Upon our return to Chicago—where we could once again sit together—we compared onboard experiences. We both remarked on how unhappy the flight attendants appeared and how each of us was separately asked whether we would like to purchase a beverage. We declined. At no point was water mentioned as an option, leaving us with the clear impression that even water came at a cost—or that complimentary water, if available at all, was deliberately left unmentioned. Overall, the experience was shocking and deeply disappointing, but it was also a profound learning experience—one we will not forget and will not repeat. -Steve

Plane was hot and miserable and the crew was rude!

12 hour delay required getting on and off plane 3 times - would have at least liked to have been offered a snack or drink

They didn’t offer a water, even after I asked

They switched our terminal 3 times and we were delayed for four plus hours!!!

It was an early flight and most people napped/slept and the crew let us which was nice.

Everything you need to know for your flight from Denver to Seattle

Information on your arrival and departure airports