Find cheap flights from Denver to Seattle

DEN - SEA

Find cheap flights from Denver to Seattle

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

Round-trip
Economy
Denver (DEN)
Seattle/Tacoma Intl
Fri 5/7
Fri 5/14
Any month
Compare vs. KAYAK |

Good to know

Low season

JanuaryBest time to beat the crowds with an average 25% drop in price.

High season

DecemberMost popular time to fly with an average 14% increase in price.

Average price round-trip

$148(avg. price over the last 2 weeks)

Good deal round-trip

$131or less

Good deal one-way

$83or less

When to book flights from Denver to Seattle

Estimated round-trip price
Average price per month
Flight prices as travel date approaches

Top tips for finding a cheap flight

  • Looking for a cheap flight? 25% of our users found flights on this route for $83 or less one-way and $131 or less round-trip.
  • The cheapest flight from Denver to Seattle was found 17 days before departure, on average.
  • Book at least 1 week before departure in order to get a below-average price.
  • High season is considered to be November, December and January. The cheapest month to fly is January.
  • Morning departure is around 11% cheaper than an evening flight, on average*.
  • Both United and Delta Airlines offer flights from Denver to Seattle that provide travelers with comfortable seats and additional legroom, as well as in-flight entertainment. If you would like to check your suitcases for free and receive complimentary snacks, opt for flying with Southwest Airlines instead.
  • If you’re traveling to Seattle for an important meeting or workshop, stop by the business center that is near the B Gates of Denver International Airport (DEN). This center provides guests with private workstations, copying services, shipping supplies, and access to the airport’s high-speed Wi-Fi.
  • To pass the time before your flight from Denver to Seattle begins boarding, go to the ZooX Public Internet Kiosk Systems in the Jeppesen Terminal of Denver International Airport. These booths allow travelers to play video games for $0.15 per minute, with a minimum payment of $3.
  • Hoping to leave one of your bags at the airport while you explore? Go to the Smarte Carte Baggage Storage desk between baggage carousels 12 and 13 of Seattle-Tacoma International Airport (SEA). In addition to offering baggage storage for $8 to $22 per item per 24h, this center also has notary and fax services.
  • To de-stress after a long day of travel, stop by the Massage Bar near the N gates of Seattle-Tacoma International Airport. 15m massages start at $18, with 30m massages costing $43. You can also have an express foot massage for less than $20.
*Average of the lowest prices shown in KAYAK’s search results for departures within the next 30 days

FAQs for booking flights from Denver to Seattle

Which airlines have a flexible cancellation policy for flights from Denver to Seattle due to COVID-19?

Which airlines apply social distancing measures on flights from Denver to Seattle due to COVID-19?

Are there Seattle travel restrictions currently due to Coronavirus?

How long does a flight from Denver to Seattle take?

How many flights are there between Denver and Seattle?

Which airlines provide the cheapest flights from Denver to Seattle?

Do I need a passport to fly between Denver and Seattle?

Which airlines fly most frequently between Denver and Seattle?

What’s the cheapest day of the week to fly from Denver to Seattle?

Which airports will I be using when flying from Denver to Seattle?

Does Denver International Airport offer any amenities for pets or service animals?

Do any airlines have lounges for their customers at Denver International Airport?

Are there any shower facilities at Seattle-Tacoma International Airport?

Where can I rent a car at Seattle-Tacoma International Airport?

How does KAYAK find such low prices 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?

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

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

Top 5 airlines serving Denver Intl to Seattle/Tacoma Intl

Scores according to KAYAK customer reviews

8.3
Alaska Airlines
Overall score based on 29,348 reviews
8.5
Boarding
8.3
Comfort
8.8
Crew
7.9
Entertainment
7.9
Food
Airline reviews

Cons: "Plane wasn’t clean (trash at my seat)"

Cons: "Dumped out in cargo to take a bus? Late late late"

Cons: "Boarding got very weird. Having B, C and D boarding groups, all of which sound the same over a loudspeaker, made for some confusion."

Pros: "Seats were comfortable and did not feel confining. Takeoff and landing were very smooth."
Cons: "Having a male flight attendant wearing makeup was off-putting. A gluten free option for snacks would be nice."

Pros: "Employees were friendly and helpful"
Cons: "Every single flight left extremely late which meant I was running through the airport to catch my connections."

Cons: "Too much time to board Seated away from my travel partner"

Pros: "Alaska airlines is terrific!!"

Pros: "Poutin"
Cons: "Higher bagge fees and missed the bus"

Cons: "I had only 40 minutes to get to my connecting flight. Then the plane was 15 minutes late. They wouldn't switch me to a seat that was open closer to front of plane and my bag was lost w important things in it that I need for this evenings show. I'm a full time musician."

Pros: "I checked my baggage with ease.The whole trip was without any inconvience. My daughter in CO made my reservations both ways thru you. I appreciated the great $fare. We will use you again . Thank You, Merry Christmas!"

Cons: "I dint know i needed a chinese visa to travel to shanhai, My flight began on denver then seattle and from seattle i wasnt able to fly to china. I received no help at all, all they did was cancel my booking not received any kind of refund and i got stuck in seattle, i had to buy new tickets to go back to denver after losing my flights and not getting a dime back, this is unacceptable!"

Pros: "On time"

Cons: "Why does it coast so much for a beer or a glass of wine??? Why is the wine glass so small?"

Pros: "Comfortable. Friendly staff."

Pros: "Did not go to seattle"

Pros: "The crew was very good."

Pros: "In flight texting for free, leg room, food"
Cons: "Nothing"

Pros: "Friendly staff"

Pros: "The crew was very nice"
Cons: "There wasn't any good offered without paying"

Pros: "Friendly people."

Pros: "The flight attendants were awesome! Very helpful and attentive.`"
Cons: "I was told that I would have internet onboard the flight. I was very much looking forward to that. When time came to connect, all I got was inflight onboard local network. No texting, no watching of football games. I would not complain had I been told up front there was no internet access."

Pros: "Seat room"

Cons: "Gate at Seattle airport was crowded. Not airlines' fault but it was tough to navigate Seattle airport."

Pros: "Dexter Alaska agent in Seattle helped get me to Portland then Medford a day late."
Cons: "Denver agents seemed not to care at all and said I could not get a hotel voucher in Seattle. Phone agent said I could get a hotel voucher because it was mechanical failure. arrived late late late into Seattle to be told there were no hotels available. I had to be insistant to get agents to make the effort to get me routed. They to me I would have no hotel and then wait until 5 pm the next day to fly to Medford. They gave no food vouchers. I had to pay for a hotel I never slept in in Medford and meals. Seems like Alaska has few flights out of Seattle and Denver and no other partner agreements to help route you. Really horrible bad experience. Not what you expect when you patly $500 plus trip insurance. Pathetic."

Pros: "We took off and we landed - nothing broke. What else is needed ?"

Pros: "Very friendly crew that understood customer service and safety"
Cons: "On a long flight would like to have known of option to purpurchase hot meal"

Pros: "Polite staff, efficient, all around great."

Pros: "Love how fast we all boarded and were situated."
Cons: "Hanging out for 30 minutes in the plane."

Pros: "Alaska Airlines treats their customers as kings and queens and not a burden like other airlines. My flights were on time, comfortable, peaceful, and most of all welcoming."
Cons: "Nothing at this time."

Pros: "Nothing"

Cons: "Delays layover very poor"

Pros: "X"
Cons: "My daughter missed her first two days back at college because of your cancelled flight. You refused to even attempt to book her on another airline. Very poor customer service."

Cons: "I wasn't able to check in early, and received an error that perhaps I didn't pay in time when I bought this months in advance. Fortunately I called early to get it sorted, but I wonder if I would have been left at the gate due to Alaska's error."

Cons: "I paid for a window seat and the seat next to it. I ended up with two aisle seats. This meant my grand-daughter and I were not sitting next to each other. NOT ACCEPTABLE"

Pros: "We got in early and everyone was friendly."

Pros: "Great airline that gets you to where you need to go on time and with comfort."

Pros: "No troubles along the way"
Cons: "No complaints/suggestions"

Pros: "Fruit and cheese platter was perfect."
Cons: "Felt very cramped. Kept getting bumped by passenger next to me and by the stewardess every single time she went up and down the isle."

Pros: "On board service was terrific."
Cons: "Flight was over an hour delayed and then there was no gate available upon arrival!"

Pros: "The overall experience was exactly what anyone would expect."
Cons: "The overall experience was exactly what anyone would expect."

Pros: "I had a connecting flight in Seattle and the gates were conveniently right next to each other which was great. The crew was awesome very friendly & helpful!"
Cons: "Just the oldness of the upolstery."

Pros: "The crew was really friendly and the seats were comfortable with more legroom in coach than most other airlines. I did not partake of food or entertainment, so gave one star because there was no box for "n/a""
Cons: "Arriving 20 minutes late to Seattle, which was the fault of the airport, not Alaska Airlines, but it still affects my rating of the trip"

Pros: "This is my first time flying Alaska. I was really impressed when one of the flight attendants offered to hang up my sport coat, even though I was sitting in coach. She even brought it to me at the end of the flight. Service was excellent, the plane was newer and very comfortable. I am a pretty dedicated fan of another airline, but after this experience I will certainly consider Alaska for future flights."
Cons: "NA"

Pros: "Great service. Crew was awesome"

Pros: "We left early and arrived early."
Cons: "Vents were weak. Way too warm."

Pros: "Service was good. Not overbooked flight"

Pros: "This is by far the most comfortable Airline I've ever flown! I'm guessing at least six more inches between seats and I could stretch out my legs!"

Pros: "The pilot was very friendly and made sure to point out landmarks as we flew over."
Cons: "The boarding crew in DIA was less than friendly, forcing people to gate-check their carry-ons. She used the claim that the flight was overbooked and 20 people needed to check their bags, then threatened to randomly take them. Meanwhile, 60% of passengers were boarding without roller bags. When I boarded the plane, which was almost full, at least half the overhead bins were empty. I had already gate checked my bag to avoid a confrontation with this pushy lady. Ridiculous!"

Pros: "Friendly"
Cons: "Should show free movies"

Pros: "Timeliness"
Cons: "Seating"

Pros: "Good"

Cons: "Luggage drop was severely understaffed. We had checked in, had boarding passes but there was a 45 minute wait just to drop off a checked bag."

Cons: "Food"

Cons: "Cheerless stewards could perk up."

Cons: "No AC for an hour before takeoff - very uncomfortable. Audio for tv did not work."

Cons: "Hour late and no wifi!"

Cons: "Nothing"

Pros: "Nothing spectacular."
Cons: "The headrests won’t stay up. And it’s hot."

Pros: "On time flight, bag made it, great price, can’t complain."
Cons: "Seat pretty tight for an average size adult man. No inflight phone charger."

Cons: "Have rhe right to carry at least one luggage per person at no cost. Besides carry on and personal item. Tickets prices and luggage costs are extremely expensive."

Cons: "The boarding process at LAX was awful. I’m sure the horrible shuttle wait and transfer from terminal to terminal is the airport’s fault, but the airline did not do anywhere near enough to inform passengers of what was in store. It was confusing and annoying."

Pros: "Easy and on time and Delta Comfort is always the best. Easy boarding process too!"

Pros: "Quick boarding process"
Cons: "Wifi stopped working halfway"

Cons: "Great"

Pros: "That we finally arrived."
Cons: "That we didn't arrive even remotely close to when we were supposed to."

Pros: "Total Experience of Flying on this Airline ."
Cons: "No Comment."

Cons: "Cramped seating for premium Econ"

Pros: "It’s was super smooth! Fast service and great customer service."
Cons: "The intercom was a little messed up."

Pros: "It was short and fast."

Pros: "Loved how close the gates were"
Cons: "Nothing"

Pros: "Delta is great"

Pros: "Delta did a really good job as always. Cheaper, more comfortable, and a WAY better experience than Alaska Airlines."
Cons: "Nothing."

Pros: "Not much . The boarding process took forever and the lines through TSA took longer .. no direction to lines and I was standing for 10 min before saying something to someone and they said o there’s another line."
Cons: "Almost everything besides the staff on the plane"

Cons: "The plane bathroom was old and junky"

Pros: "Movies"
Cons: "Lack of legroom in economy"

Cons: "Food was bad."

Cons: "Poor WiFi. Paid extra to get it, but didnt sporadic at best."

Pros: "None of it!! Poor selection"
Cons: "All of it. Again poor selection"

Pros: "Boarding super excellent! Also: Best landing I've ever experienced! Props to the pilot!!"

Pros: "Newer plane with movies."
Cons: "Airlines pack you on so tight."

Cons: "There was a kid screaming on both flights and t was not a good time"

Pros: "Nice and attentive staff, smooth on and off."

Pros: "Excellent crew and comfortable flight"

Pros: "The moviea"
Cons: "The time of night"

Pros: "Boarding was easy"
Cons: "Arrived 15 mins late and then taxied for another 5-10 mins."

Cons: "I was starving because of my short connection time and couldn't have lunch - wanted to eat something solid and they just had boxes with fruits and cheese."

Pros: "I always have a great experience on Delta! Thank you"

Cons: "So so food. Terrible delay leaving Beijing. Gatemoccupied in SEA."

Pros: "The flight attendants were so nice and accomadating. Even came by to refill our waters! I've never been on a flight with such friendly flight attendants!"

Cons: "Snacks if possible"

Cons: "horrible boarding management in SJC."

Pros: "Bags arrived on the belt quickly"
Cons: "Why is there not saying precheck to use after you've been funneled through customs? ATL is advanced enough to have kiosk for arrival, even for those confused and not with global entry, but then forces you to wait in security line instead of the typically faster tea precheck line. Every minute I'm in line, I'm not spending money"

Pros: "All went well"
Cons: "Nothing"

Pros: "Very informative staff"
Cons: "Was late"

Cons: "I drove 5 hours to get to the airport and unfortunately ended up delayed because of traffic and slow shuttles from parking. I arrived 1 hour before the flight, but security was so slow I didn't get to the gat until 10 minutes before arrival. There were no gate agents present and despite banging on the gateway door and other Delta agents at the adjacent gate, no one helped me. I can only surmise that they had already given away our seats, which were award tickets, GAINED BY BEING A LOYAL DELTA CUSTOMER. The gate agents were unapologetic and useless at rebooking, and I bought a ticket from Southwest instead. As i was trying to get to my sister's wedding, and repeatedly told the agents this, their behavior was particularly abominable. DELTA, YOU'VE LOST A LOYAL CUSTOMER."

Cons: "Enforce your baggage size and number limits. A significant number of passengers take bags onboard that are oversized."

Pros: "The landing experience."
Cons: "The organization of serving meals."

Pros: "Excellent customer service. That doesn't seem to happen too often with airlines. Delta has been outstanding."
Cons: "No complaints."

Pros: "on time travel care in treating my visitors from Kenya Africa"

Pros: "Yes made sure mask was in place"
Cons: "No"

Cons: "Overbooked and crowded, on a Sunday."

Cons: "Everything was dandy!"

Pros: "Nothing."
Cons: "Everything"

Pros: "Nothing"
Cons: "Everything"

Cons: "You were out of earphones"

Pros: "We were allowed to board early with my father, who is disabled."
Cons: "Denver airport was a nightmare with my disabled father. We were given a “wheelchair” but no escort through a nightmarish security scene. Airport is terribly designed, lacking clear signage and navigation. TSA was a disaster and no one seemed remotely concerned about my father’s comfort or needs."

Cons: "Better snacks."

Cons: "Wider seating"

Pros: "nice entertainment when you use the AA app."
Cons: "Unbelievable turbulent and bumpy ride. Not AA's fault but the question was "how was the trip?" It was a white-knuckle ride."

Pros: "that it's over."
Cons: "sat on tarmac for 45 minutes! AFTER landing... unacceptable."

Cons: "Less boarding groups"

Cons: "Well organized loading, consistent beverage service"

Cons: "I have changed flights. Been delayed 5 times now. And still haven’t left the USA."

Cons: "Weather related, mostly, so not AA’s fault"

Cons: "I researched and called and found a 45L backpack so I could carry on my dive bag. That’s the reason I’m going all the way to Fiji. Not letting me get it in LA I’d also ridiculous."

Cons: "They have very long and annoying credit card announcements"

Cons: "Delay due to equipment failure, were not able to estimate delay"

Pros: "Nothing."

Pros: "Not using kayak"
Cons: "Kayak booked me the worst itinerary in the history of air travel!"

Pros: "The helpful steward"
Cons: "The bumpy ride"

Pros: "Both the departing and returning flights departed in schedule and arrived a solid half hour early. Staff was accommodating and friendly, and very helpful with me juggling luggage and a toddler by myself."

Cons: "No outlet and waited idle for a long time before getting to get off plane also had to walk my bag back bc there was no overhead storage space in the bins which prevented me from getting off the plane sooner"

Pros: "Boarding moved along well, even though there wasn’t special boarding for families with young children. The plane was really comfortable (new 2x2) and the staff was really friendly."

Pros: "Food and entertainment were great"

Pros: "Early for arrival!! Love that!"

Pros: "Everything was on time and handled efficiently and courteously. I was pleased with everything."

Cons: "no charging station"

Cons: "Too cold, even with air off above me."

Pros: "All good, except poor prep on food"
Cons: "As above"

Cons: "It took a while day to get our bags after they decided to put it on the next flight"

Pros: "Good connection"

Cons: "This agent spent 30+ min to check us in through a connection flight to Seattle. He couldn't find my wife's reservation, when it should be in the same reservation as me. He tried 5 times, and still failed. Later we found out at the gate that he was using the wrong name (same last name, different first name). Luckily the American Airline agent at the gate was more than competent and efficient to correct the issue in 5 min."

Cons: "Maintenance problems, late departures, uncomfortable airlines"

Pros: "Everything"
Cons: "Nothing"

Cons: "Dry / borderline rude staff and hostess. Dated plane. Tiny seats. But that is pretty much the baseline of airlines in the US. When will carriers start to take note from International carriers..leaps and bounds ahead."

Pros: "Nothing"
Cons: "Everything"

Pros: "Long walk and less than an hour. Very difficult for senior. No assistan e available."
Cons: "The pain from carrying bag between gates"

Pros: "Delayed"

Cons: "Longer flights should have screens in the headrests"

Cons: "Going through immigration in Dallas is a disaster. The wait is eternal. None-US passengers seemed to get processed faster."

Pros: "Wi fi did not work."

Pros: "The Denver airport is beautiful"
Cons: "I will never fly AA again - see below"

Pros: "Free beverage"
Cons: "My bag was lost and it still hasn't showed up at the airport. Seems like I would get some kind of credit of some kind for this inconvenience."

Pros: "The pilot was charming, and really hugged Mt. Rainier on the way in - Made for an incredible view in the moonlight!"

Cons: "Delays"

Pros: "Friendly service"
Cons: "Snacks"

Pros: "Nothing"
Cons: "See above comments"

Pros: "how easy it was to purchase ticket on kayak."
Cons: "Being charged for my checked bag unexpectedly at check in."

Pros: "Space security manners"

Pros: "Nothing"
Cons: "Out of the four frontier flights I’ve taken in the past six months each one has been delayed for some reason. First one was over an hour late and caused a majority to miss connecting flights. Today’s experience was not a whole lot different. First leg of the trip was behind schedule, second was delayed at the terminal for the “cleaning” of the aircraft. I will walk to my destination before ever flying with frontier again"

Cons: "It’d be nice to have internet access, whether free or for purchase"

Cons: "Delays"

Pros: "I arrived."
Cons: "It was an hour after boarding before take off. Another 15 minutes on the ground after landing waiting for a gate at midnight on a weekday. I understand that circumstances occur beyond the airlines control, but this has been routinely occurring on my trips with Frontier. Absent compelling reasons, I will not be flying with them again."

Pros: "They still pick up trash!!"
Cons: "New airbus has even LESS room!! Have to manhandle your personal bag out of the even smaller space under the seat! A soda is $3! There is Nothing to read anymore and the crew are overwhelmed with cranky people... making them cranky."

Pros: "The same"

Pros: "The crew"
Cons: "The web page to bundle was very hard to manover Wasn't asked about payment for my carry on till it was to late How and when can you bundle?"

Pros: "As above."
Cons: "As above"

Pros: "I was last on and only the 1st class was open so free upgrade"
Cons: "No complimentary snacks"

Pros: "fare was good"
Cons: "the seat was terrible"

Pros: "* Good leg room at my seat * Though the check-in line was very long, the curbside check-in attendant was courteous, professional, and very efficient."
Cons: "* Long line for check in * Flight 137 from Denver to Seattle was almost two hours late * seats on airplane don't recline and there is not an adjustable headrest to hold my head in place * The flight attendant wouldn't let me put my paid-for carry-on luggage in the overhead bin above our seats (we were sitting in row 2, seats A,B, C). She said they were reserved for row 1. So I had to place our paid-for carry-on baggage in the overhead bins above row 4. * no movie or even reading material at my seat * No complimentary snack or beverage (only available for purchase). Are you kidding me? I paid extra money for carryons and check-in baggage for all three of us, and my experience on Frontier made me feel like a second class citizen. I doubt I will ever fly with Frontier again."

Cons: "Frontiers prices might look good upon booking but you are charged for everything. $45 extra for a carry-on, $2.95 for a can of soda, etc... cramped seating,"

Pros: "the cost and my bags did make is to my destination."
Cons: "The ticket counter was chaos and the baggage drop was worse. WOW can we have some consistency and harmony. Oh and do not throw my bags when you put them on the belt especially not in front of me and after you charged me $95 for 2 bags. Shame shame how would you like that with your personal baggage? hmm. Boarding felt like even more chaos they didn't give people time and it was like they tried to heard cattle. Very much not OK. We just paid to get treated like this. Hmm. Comfort- Not so much felt like I was on a bench seat . Food. Ridiculous here is water everything else you get charged for."

Pros: "Nothing"
Cons: "Everything"

Pros: "Crew was friendly and accommodating but we waited 3+ hours for a pilot that never showed"
Cons: "Crew was friendly and accommodating but we waited 3+ hours for a pilot that never showed"

Pros: "same as above"
Cons: "same as above"

Pros: "Staff was awesome and efficient"
Cons: "Food options, especially since one has to purchase snacks."

Pros: "I really appreciated the free checked bags. That helped me out a lot on my trip. Thank you, Frontier!"

Pros: "Staff was friendly."
Cons: "No food or entertainment and nickle and dimed on everything."

Cons: "From the time my flight sat at the gate for 30 minutes saying that had to load last minute bags, to getting no water to drink for 3 hours, to uncomfortable seats that do not push back, and now no bags after 36 hours after paying a $40.00 fee, with no way to communicate with the airlines for a status, this will be the last Frontier flight for me, regardless of the pricing."

Cons: "I felt taken advantage of by the surcharges."

Pros: "Cheap prices"
Cons: "Being stalled on the tarmac for over an hour arriving to Denver. People missing connecting flights. Plane arriving late leaving from Denver to Seattle. No complimentary beverages."

Pros: "speed on check in, age and competent attitude of stewards(esses), clean passenger area."

Pros: "See above."

Pros: "It was quick and done."
Cons: "The horrible delay. It seems Frontier has issues in communication perhaps? My flight before we sat on the tarmac for AN HOUR after a 40 delay at take off. REALLY screwed up my schedule."

Cons: "Charge for carry-on bags. Charge for seats. Nickel and dime website trying to upsell you on every screen. Seats don't recline, uncomfortable."

Pros: "Nothing"
Cons: "Canceled my flight 30 min before takeoff, and didn't get us on another one for 2 days."

Cons: "Charging for carry ins makes me never want to fly frontier again"

Cons: "Frontier canceled my return flight And could not book me on the return flight until two days later. They have no partners or affiliates, so they couldn't even book an alternative return flight on the same day ."

Cons: "I wish the headrest had those little flaps you can fold up to rest your head on--would have made the fact that the seats don't recline better."

Pros: "The announcement (although I didn't take them up on it) to offer two domestic round trips if I'd sign up for one of their Mastercards. It's probably not a bad deal for someone who likes to have lots of credit cards and doesn't mind annual fees, I'm just not one of those people."
Cons: "My inability to access their e-mail offers to set things up ahead of time and at lower costs than paying them at the airport check-in, above and beyond the baggage charges themselves (Seventy bucks), especially for my carry on ... COME ON! I've become used to Southwest's far more enlightened policies, which I obviously prefer. Since it also has flights between Seattle and Denver, I'll look much more closely at staying with them the next time I make this trip."

Pros: "Airbus jet was nice. Frontier credit card sign-up was offered."

Cons: "The fees for seat assignments and carry on luggage. Frontier also does not accept TSA Pre-check."

Cons: "They charge for carry on baggage and do not make you aware of this at the time of ticket purchase, so it is a surprise. They do not provide even free water in-flight; everything, including even water, is for purchase. Water should really be free. The initial prices are therefore misleading since they tack on many additional fees that are not standard in the airline industry."

Pros: "speedy, safe, and friendly"
Cons: "no complimentary drink or snack. seats where uncomfortable"

Cons: "I didn't like the fact that there was no notification from a third party vendor that there were extra charges for baggage (including carry on) and seat selection. If I had known about these charges at the point of purchase, I could have made a better informed decision."

Pros: "Letting me in though I got a bit late to the gate, due to unexpectedly log TSA lined"

Cons: "EVERYTHING WAS OVER PRICED AND DOUBLED, And i tryed too changed my flight because of a family emergency, and was DOUBLED my original ticket."

Cons: "It's just the cheapest option, and they pretty much surprise you with a ton of random fees that you aren't told about when purchasing the ticket. It's sneaky and annoying and I don't have respect for this airline. Not to mention that the seats lack comfort, there is little to no legroom, no tray tables, and no complimentary drinks. Bummer-- I'm sticking with Alaska Airlines from now on."

Cons: "Paying for seat AND baggage is reason to fly Southwest."

Pros: "The stewards and stewardesses were extremely professional"
Cons: "I don't like that Frontier does not have staff easily found at the airport to address concerns regarding the flight/delays/luggage issues that arise and if calling them direct there is at least a 20 to 30 minute delay before being able to speak with anyone regarding your issue while you wait on hold"

Pros: "same as above"
Cons: "same as above"

Pros: "See cooment above"
Cons: "See comments above"

Cons: "My name was not correct on return email documents. When I tried to correct on-line, the program asked for another $139. When I phoned the number listed, I had a gentleman whose English was very hard to understand. He ended up telling me not to worry about the error-it would not cause a problem. I ended up phoning a 2nd time, to another person to assure that nothing would go wrong at boarding time."

Pros: ".It was a very confortable flight and right on time.."

Pros: "Arriving to my destination"
Cons: "If I wanted to pay $200 more for my flight not this "good deal" I would have flown United and payed up front so it was budgeted. I have never flown Frontier so I didn't know I was going to be getting taken both coming and going just for a seat reservation! Bags! Checking in early! NOT A DEAL"

Cons: "All Frontier flights were cancelled for 2 days straight, therefore I had to book with another airline."

Cons: "Finding that getting a seat costs extra"

Cons: "My mother did not get one of her bag back when we arrived in Seattle"

Cons: "Uncomfortable seating"

Pros: "Fast"
Cons: "No"

Pros: "Nothing right now"
Cons: "Professional people attending the customers."

Pros: "Good legroom, they waited for the late passengers(it wasn’t just me!)"
Cons: "Free bev"

Pros: "Price"

Pros: "ㅑ"

Pros: "Cheap n effective"
Cons: "Airport work"

Pros: "Constantly crying babies and speakers are ear piercing loud."
Cons: "Crying babies"

Cons: "no wifi"

Pros: "lost luggage"

Pros: "The price but it wasn't worth it."
Cons: "The cramped seating."

Pros: "Easy. Will fly spirit again."

Pros: "Nothing"
Cons: "Everything"

Pros: "it was sufficient"
Cons: "charged for bag at check in."

Pros: "Nothing"
Cons: "Nothing"

Pros: "Got in early despite a few minute delay boarding."

Pros: "Price"
Cons: "Comfort packed like sardines"

Cons: "I didn't get a refund"

Pros: "We got to our destination safely"

Pros: "Staff was super friendly and helpful!"

Pros: "Nothing"
Cons: "The dont have it anywere during booking process that not a single bag will be allowed onboard. (i mean even a hand baggage). After that they say that they have it mentioned on the boarding pass. I dont think anyone reads that in particular. More over when i checked the lady did not have a problem. The lady a the boarding brigde wanted a 100 dollars just becuase we had 1 hand bag. Pure cheating."

Pros: "The personnel was personable."
Cons: "Everything, truly everything. Awful plane, awful prices, not good."

Pros: "I liked everything about Spirit!"
Cons: "Super"

Cons: "Luggage fees."

Pros: "Delayed"
Cons: "Being delayed"

Pros: "Cheap"
Cons: "Uncomfortable"

Pros: "Nothing"
Cons: "Everything"

Pros: "Affordable and easy. Thanx :)"

Pros: "Friendly staff"

Cons: "Alaska would've been a much better and more economical choice. Had no idea Spirit charges for bags until after I bought the ticket through Khyak. They might've said something! Also, Alaska has free carryons, diet cokes and peanuts. Spirit won't be around long."

Cons: "Delayed so much had to cancel trip."

Cons: "Bag fee are excessive plus 40 lbs maximum for bags is not competitive with other airlines."

Cons: "I will never waste my money on spirit ever again."

Pros: "Good value. Absolutely no bells and whistles."
Cons: "Perfect for a very short trip. Bring your own everything."

Cons: "Smaller than usual seat space"

Pros: "Nothing"
Cons: "Everything"

Cons: "Long lines, poor service, lack of communication w/ passengers"

Cons: "Mediocre at best.... only used Spirit because it was the cheapest option.... $50 bag check changed that... won't fly spirit again"

Pros: "Price. Everything went smoothly."
Cons: "Nothing comes to mind."

Cons: "I didn't like that there wasn't an app to do your tickets to go paperless!"

Pros: "I liked that the one hour and 56 minutes layover in FL was only less than an hour. I liked that the pregant woman who had a child less than two years of age seated on my left and the mother of the mother seated to my right whose child was less than a year old was considerate enough of the rest of the passengers to go above and beyond to try to keep their children quiet. They endured very much uncomfortable positions due to lack of space to suceed and meet their expectations of child quietness . they both get a well done from me. It could have been a big noisey problem."
Cons: "we were an hour late taking off from Denver."

Cons: "Extremely long delay"

Pros: "Nothing."
Cons: "Everything. Rude staff, terrible."

Cons: "How a passenger in a wheelchair was treated rudely and completely ignored."

Pros: "tome schedule"
Cons: "amount for my luggage......complete rip off"

Pros: "The pilot got the plane to Chicago over 30 minutes early."
Cons: "Spirit allows passengers to bring a purse for free everything else is an additional charge. The plane was really dirty."

Cons: "Everything I didn't like it"

Pros: "Should be illegal"

Pros: "I liked that Spirit upgraded me to a window seat with no cost and that there were no delays."
Cons: "No dislikes"

Cons: "Same as above"

Pros: "Price."
Cons: "Very little leg room for even a smaller person. Spirit flights are consistently delayed for technical issues."

Read more about Alaska Airlines
COVID-19 information

Safety measures for airlines flying from Denver to Seattle

Airlines flying from Denver to Seattle have enacted additional safety measures and adjusted policies to better accommodate travelers. Policies vary by airline.

Heightened sanitation

Daily cleaning, installation of cabin HEPA filters on flights from Denver to Seattle

Mandatory masks

Masks required on board, masks provided on flights from Denver to Seattle

Social distancing seating

Middle seats unavailable to book on flights from Denver to Seattle

Pre-flight testing

Testing for antibodies, testing for symptoms for flights from Denver to Seattle

Book cheap flights from Denver to Seattle

Recent round-trip flight & train deals

5/16
Sun
nonstop
Frontier
3h 00m
DEN - SEA
5/19
Wed
nonstop
Frontier
2h 44m
SEA - DEN
5/18
Tue
nonstop
Frontier
3h 04m
DEN - SEA
5/20
Thu
nonstop
Frontier
2h 42m
SEA - DEN
5/16
Sun
nonstop
Frontier
3h 00m
DEN - SEA
5/20
Thu
nonstop
Frontier
2h 42m
SEA - DEN
5/13
Thu
nonstop
Frontier
3h 00m
DEN - SEA
5/19
Wed
nonstop
Frontier
2h 44m
SEA - DEN
5/22
Sat
1 stop
Multiple Airlines
6h 33m
DEN - SEA
5/24
Mon
nonstop
Multiple Airlines
2h 45m
SEA - DEN
5/14
Fri
nonstop
Multiple Airlines
2h 57m
DEN - SEA
5/18
Tue
nonstop
Multiple Airlines
2h 44m
SEA - DEN
5/14
Fri
nonstop
Multiple Airlines
2h 57m
DEN - SEA
5/19
Wed
nonstop
Multiple Airlines
2h 44m
SEA - DEN
5/11
Tue
nonstop
Frontier
2h 59m
DEN - SEA
5/18
Tue
nonstop
Frontier
2h 44m
SEA - DEN
5/13
Thu
nonstop
Multiple Airlines
2h 57m
DEN - SEA
5/16
Sun
nonstop
Multiple Airlines
2h 42m
SEA - DEN
5/14
Fri
nonstop
Delta
3h 17m
DEN - SEA
5/15
Sat
nonstop
Delta
2h 47m
SEA - DEN
7/3
Sat
1 stop
Amtrak
60h 51m
EN8 - EA9
7/7
Wed
1 stop
Amtrak
53h 53m
EA9 - EN8
6/2
Wed
1 stop
Amtrak
60h 51m
EN8 - EA9
6/6
Sun
1 stop
Amtrak
53h 53m
EA9 - EN8
5/31
Mon
1 stop
Amtrak
60h 51m
EN8 - EA9
6/4
Fri
1 stop
Amtrak
53h 53m
EA9 - EN8
6/17
Thu
1 stop
Amtrak
60h 51m
EN8 - EA9
6/21
Mon
1 stop
Amtrak
53h 53m
EA9 - EN8
5/28
Fri
1 stop
Amtrak
60h 51m
EN8 - EA9
6/8
Tue
1 stop
Amtrak
53h 53m
EA9 - EN8
7/3
Sat
1 stop
Amtrak
60h 51m
EN8 - EA9
7/9
Fri
1 stop
Amtrak
53h 53m
EA9 - EN8
5/28
Fri
1 stop
Amtrak
60h 51m
EN8 - EA9
6/4
Fri
1 stop
Amtrak
53h 53m
EA9 - EN8
6/4
Fri
1 stop
Amtrak
60h 51m
EN8 - EA9
6/8
Tue
1 stop
Amtrak
53h 53m
EA9 - EN8
7/5
Mon
1 stop
Amtrak
60h 51m
EN8 - EA9
7/9
Fri
1 stop
Amtrak
53h 53m
EA9 - EN8
6/26
Sat
1 stop
Amtrak
60h 51m
EN8 - EA9
6/29
Tue
1 stop
Amtrak
53h 53m
EA9 - EN8
Show more results

Search by stops

Search by airline

Search by train company

Recent one-way flight & train deals

5/22
Sat
nonstop
Frontier
3h 04m
DEN - SEA
5/13
Thu
nonstop
Frontier
3h 00m
DEN - SEA
5/18
Tue
nonstop
Frontier
3h 04m
DEN - SEA
5/19
Wed
nonstop
Frontier
2h 59m
DEN - SEA
6/2
Wed
1 stop
Spirit Airlines
12h 34m
DEN - SEA
5/18
Tue
1 stop
Spirit Airlines
12h 34m
DEN - SEA
5/14
Fri
nonstop
Delta
3h 17m
DEN - SEA
5/21
Fri
nonstop
Alaska Airlines
2h 55m
DEN - SEA
5/11
Tue
1 stop
Multiple Airlines
13h 48m
DEN - SEA
5/14
Fri
1 stop
American Airlines
10h 08m
DEN - SEA
5/31
Mon
1 stop
Amtrak
60h 51m
EN8 - EA9
5/31
Mon
1 stop
Amtrak
60h 51m
EN8 - EA9
6/17
Thu
1 stop
Amtrak
60h 51m
EN8 - EA9
6/14
Mon
1 stop
Amtrak
60h 51m
EN8 - EA9
6/7
Mon
1 stop
Amtrak
60h 51m
EN8 - EA9
6/4
Fri
1 stop
Amtrak
60h 51m
EN8 - EA9
6/17
Thu
1 stop
Amtrak
60h 51m
EN8 - EA9
5/26
Wed
1 stop
Amtrak
60h 51m
EN8 - EA9
5/26
Wed
1 stop
Amtrak
60h 51m
EN8 - EA9
7/19
Mon
1 stop
Amtrak
60h 51m
EN8 - EA9
Show more results

Compare transportation modes for Denver to Seattle

Average price
Flights $297
Trains $394
-
1
  • Round-trip
  • One-way
  • Multi-city
  • Trip Builder
  • Economy
  • Premium Economy
  • Business
  • First
  • Multiple
Economy
  • Economy
  • Premium Economy
  • Business
  • First
Economy
  • Economy
  • Premium Economy
  • Business
  • First
Economy
  • Economy
  • Premium Economy
  • Business
  • First
Economy
  • Economy
  • Premium Economy
  • Business
  • First
Economy
  • Economy
  • Premium Economy
  • Business
  • First
Economy
  • Economy
  • Premium Economy
  • Business
  • First