Find cheap flights from Washington to Colorado from $51

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight departing on 7/12. 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.
Round-trip
1 adult
Economy
0 bags
Fri 7/7
Fri 7/14

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Good to know

Low season

January

High season

June

Cheapest flight

$51

Average price round-trip

$460

Good deal round-trip

$58

Good deal one-way

$34
Best time to beat the crowds with an average 6% drop in price.
Most popular time to fly with an average 16% increase in price.
Flight from Seattle to Denver
(avg. price over the last 2 weeks)
or less
or less

FAQs for booking flights from Washington to Colorado

Top 5 airlines serving from Washington to Colorado

Scores according to KAYAK customer reviews
8.3
Alaska AirlinesOverall score based on 29427 reviews
79food
85boarding
88crew
83comfort
79entertainment
85overall
Airline reviews
Pros: "Nice quiet flight"
Cons: "Crew member attitude specifically regarding passengers in the emergency rows"
Read more about Alaska Airlines
Pros: "Nice quiet flight"
Cons: "Crew member attitude specifically regarding passengers in the emergency rows"
Pros: "This is always a quick flight. They usually only serve OJ and water, but the time goes by that it doesn’t matter!"
Pros: "Friendly crew, easy boarding and getting off plane. Efficient and wonderful overall"
Pros: "Flight crew was nice"
Cons: "They were careless with our suitcases. When we got to Vancouver, we were missing wheels on our suitcases. 2 wheels on my husband's and 1 on mine. It made it horrible to pull the suitcases."
Pros: "Timeliness"
Cons: "If alcohol is served on a short flight I recommend getting through drink service faster. I did not appreciate getting my beer at the end (because I was at the back of the plane) and 5 minutes later the crew asking for it back because we were landing soon."
Pros: "Crew was great, the flight was good. Food is good but expensive."
Cons: "Free or inexpensive food options would be nice. I also prefer when the screens are in the back of the seat and I don't have to stream on my phone or pay high prices to use data."
Pros: "Crew were very attentive and hospitable to the crew. I have been flying ASIANA many times and enjoy the flight as well."
Pros: "Person next to me was pleasant."
Cons: "Seats hard and uncomfortable, head rests didn't go up. Plane did appear to be new."
Pros: "Bryan was my steward on flight 1402 from Seattle to Portland and he was so kind and helpful. Will fly again just because of him."
Pros: "Polite crew :)"
Cons: "Pretzels!!! Seriously, the Biscof cookies are not as good. Of course, I like salty :)"
Cons: "Wouldn’t change a thing! I don’t always fly! But when I do!! I fly delta!!"
Cons: "For options none. No drink carts at all. Had coffee once after I asked. Poor quality entertainment. Just a huge waste of money."
Pros: "Crew was super amazing and friendly! Very good service also!"
Cons: "No seat back entertainment.."
Pros: "Crew was awesome! Service was quick!"
Cons: "One flight the plane was quite warm and the air overhead was blowing warm air.. didn’t cool down until we were preparing to land and then it blew warm air out again.."
Pros: "Boarding process need to be improved. Seat assignment is horrible"
Pros: "The staff at Delta are always friendly and helpful and they were able to squeeze me onto a very full flight."
Cons: "It was fabulous as always! Thank you. I love Delta!"
Pros: "Crew was good. No economy seat is super comfortable. (Why would you even ask that?)"
Cons: "Be on time. Not keep changing/delaying the border time. Not change my seat. (Plane was far from full.)"
Pros: "Seats too small"
Cons: "Crappie entertainment. Never figured out how to login on phone,"
Cons: "Flight into Seattle delayed, flight out of Seattle to Minneapolis delayed flights out of Minneapolis to Bismarck delayed. Ran from gate F to gate c24 arrived at 10:23 p.m. Slight to the park at 10:25 p.m. and they closed the door on me as I was running up there. Ran across the entire terminal to get there and they would not let me on. Last Flight of the night to Bismarck. Missed my uncle's 90th birthday party. Would not give me food voucher. Delta gate agent told me she would lose her job if she did not close the doors 8 minutes prior. However the Minneapolis flight waited for 15 minutes for people to board that plane. How does that compute? Why would they not wait 3 minutes for me rather than pay the money to put me up in a hotel?"
Cons: "Delays could have been communicated better. My overhead light wasn’t functional."
Pros: "The crew was great!"
Cons: "I had to take a bus from my gate to the plane from the new D21-26 gates."
Pros: "The people were nice and it felt like a quick flight."
Cons: "There was no one at the check-in desk when I got to the airport and when someone called to ask when they would be there Sun Country said they come 2 hours before the flight. Giving people an hour to get through security and get to they're gates before boarding. I also should have looked at how much it would cost checking a bag($20) and all the additional costs that Sun Country has (seat: $7-$25)."
Pros: "Price was reasonable."
Cons: "The lady at the check in counter was unfriendly - gave me hard time communicating with me."
Pros: "Once we got on board all was well."
Cons: "That we couldn’t get boarding passes online without buying a seat. We arrived from an Alaskan cruise about 6 hrs early and had to wait until 2 hrs before our flight, when a ticket agent arrived, before we could get where we could get food to eat. Then the security line was unbelievably long and we just got through shortly before our flight. Luckily there was a bagel shop right next to the boarding area."
Pros: "I made it safely in one piece and my luggage did too."
Cons: "There was very very little room in the seats. I have never been so cramped on a flight. My knees were hitting the back of the seat in front of me even before I tried to slouch down and take a nap. The seats were also very firm. My butt cheeks fell asleep multiple times so I had to shift in my seat but I couldn’t move very far because my knees were pinned."
Pros: "Nothing"
Cons: "The flight was the worse we've ever had. Had us running from north concourse to the south concourse for at least a mile& then busing us back to the north to board the plane. No room in our seats, one drink cart, &not able to put anything up in the overhead without paying $30 dollars. Having to pay for a small crummy seat that left our legs cramped after a 3 hour flight. I shutter at the thought of our return flight home! NEVER AGAIN will we fly Sun Country!"
Pros: "I loved how, once the aircraft was there they updated us and got everyone organized during the boarding process and we left in a reasonable amount of time after the aircraft arrived. I didn't have any problems with the flight, and it was nice to be notified in advanced about the upcoming turbulence."
Cons: "It was late, and with my long layover, I couldn't check-in without exiting the secure area. They are understaffed, and they don't have anyone in the secured area to even ask questions too, let along check in passengers that are transferring from other airlines. Also, there wasn't anything showing the passengers that the flight was delayed until 10 minutes before the flight was supposed to leave. I knew it was late, only after the agent from a different airline did many searches into my connecting flight, and I also asked my check-in agent at Sun Country, I had to ask! That information was not given willingly."
Cons: "The plane was held an hour and a half for some tourist group to show up. After we landed the stuwartists thanked the tour group for flying with them. There was consideration for the rest of the plane."
Cons: "While the cart was parked next to me the flight attendant dropped a can of soda which splattered on my jacket, shirt, pants, feet and shoes - needless to say, I wasn't happy to be wearing soda for the next 10 hours. While she did apologize, their just wasn't any heart, concern or follow-up on it. No steps to give me water or napkins to clean myself up. Very disappointing."
Cons: "Too much to write down. Start at the counter and work yourself to the plane. I hope you get it right eventually, I’ll be flying Southwest"
Cons: "There are too many announcements on the screen before you can start watching entertainment. It takes about 15 minutes."
Pros: "The staff at seatac airport were condescending and not helpful...traveling with a service dog and made to pay the pet fee and talked about me where I can over hearnthen in a manner that embarassed me"
Pros: "The food and the crew totally good"
Cons: "Maybe the toilets, need to be clean at least once in a flight"
Pros: "Crew was super nice"
Cons: "Airline to be more user friendly with connecting to free entertainment"
Cons: "Entertainment. If the crew communicated with each other. There were multiple incorrect announcements."
Cons: "My tv didn’t work my WiFi didn’t work and no beverage service"
Pros: "Boarding crew in Spokane was friendly and very efficient."
Cons: "There were no snacks - they told us they “ran out” on the previous flight and hadn’t refilled yet."
Cons: "Business class - never offered food or drink for entire flight."
Pros: "Crew was efficient and pleasant making for a good experience."
Cons: "Nothing"
Pros: "Everyone was nice and helped with any questions I had"
Cons: "Logging into the internet from the iPad"
Pros: "The crew was nice. When I finally arrived in Denver, Marlin in customer service was the only saving grace for United for me. When I asked for options for an earlier flight into Rapid City so I didn’t have to wait 24 hours and miss my visit with my sister, he looked at different hubs (Chicago, Minneapolis) to see if they had any available flights into Rapid, he checked for double bookings, and when he couldn’t find anything, he put me on the standby list for the first flight out in the morning and wrote down the flight information for all of the United flights from Denver for the following day. Marlin provided excellent customer service and was a huge credit to the company."
Cons: "The flight was supposed to leave at 3:56 pm and didn’t leave until 7:30 pm. I would estimate at least 15-20 people missed connecting flights because of the delay. According to the United app, the delay initially started in Portland due to mechanical issues, which took over 3 hours. Then, there was a weather delay in San Francisco according to the gate agent - there was a ground hold and no planes were landing or flying out. At some point, I would think another plane would have been an option rather than delaying a flight for this long and disrupting holiday travel for so many people."
Pros: "The crew were friendly and attentive"
Cons: "Delays were caused because the captains lost the fuel sheet and calculated the remaining furl incorrectly. we were delayed 45 minutes for this."
Cons: "ran out of the food i wanted. poor selection of food... screen on "tv" was too dark to see details"
Pros: "Was able to get on another flight"
Cons: "If they could have held the flight for 15 minutes, I would have made it. My flight from Spokane was late. Now I had to pay another $250 just for a crappy room for the night."
Pros: "I watched a good movie."
Cons: "The plane seemed old. Food was pretty lousy. Hummus was dry, crackers were stale."
Pros: "I liked the ticket price."
Cons: "The seat was very narrow with absolutely minimal leg space, and a carry-on bag was not included in the fare."
Pros: "On time."
Cons: "Could my knees get just one more inch? Why am I tolerating a seat designed for a short person?"
Cons: "Delta Global Services is the contract company for UA and Delta in MISSOULA. After a great flight to MSO from Denver, we have been sitting in the plane while DGS tried to figure out how to get us off the plane. No management is here to make decisions. Horrible company that is managing United’s flight"
Cons: "A smile from the flight attendant and something other than pretzels in first class."

Book cheap flights from Washington to Colorado

Recent round-trip flight deals

9/16Sat
nonstopFrontier
2h 55mSEA-DEN
9/30Sat
nonstopFrontier
3h 06mDEN-SEA
$100
9/9Sat
nonstopFrontier
2h 54mSEA-DEN
9/12Tue
nonstopFrontier
3h 01mDEN-SEA
$109
9/13Wed
nonstopFrontier
2h 55mSEA-DEN
9/22Fri
nonstopFrontier
3h 06mDEN-SEA
$110
8/23Wed
nonstopFrontier
2h 40mSEA-DEN
8/27Sun
nonstopFrontier
2h 58mDEN-SEA
$112
9/26Tue
nonstopFrontier
2h 54mSEA-DEN
10/14Sat
nonstopFrontier
3h 07mDEN-SEA
$115
10/28Sat
nonstopFrontier
2h 45mSEA-DEN
11/13Mon
nonstopFrontier
3h 13mDEN-SEA
$118
8/2Wed
nonstopFrontier
2h 45mSEA-DEN
8/7Mon
nonstopFrontier
3h 05mDEN-SEA
$119
9/28Thu
nonstopFrontier
2h 54mSEA-DEN
10/5Thu
nonstopFrontier
3h 07mDEN-SEA
$120
7/26Wed
nonstopMultiple Airlines
2h 45mSEA-DEN
8/29Tue
1 stopMultiple Airlines
5h 52mDEN-SEA
$129
9/2Sat
nonstopMultiple Airlines
2h 40mSEA-DEN
9/4Mon
nonstopMultiple Airlines
3h 04mDEN-SEA
$138
7/19Wed
nonstopMultiple Airlines
2h 45mSEA-DEN
7/25Tue
1 stopMultiple Airlines
12h 49mDEN-SEA
$142
9/26Tue
nonstopUnited Airlines
2h 17mGEG-DEN
10/2Mon
nonstopUnited Airlines
2h 24mDEN-GEG
$146
7/22Sat
nonstopAlaska Airlines
2h 39mSEA-DEN
7/24Mon
nonstopAlaska Airlines
2h 58mDEN-SEA
$146
8/30Wed
1 stopMultiple Airlines
7h 18mSEA-DEN
9/5Tue
nonstopMultiple Airlines
2h 58mDEN-SEA
$147
7/31Mon
nonstopDelta
2h 38mSEA-DEN
8/8Tue
nonstopDelta
2h 59mDEN-SEA
$154
9/9Sat
nonstopAlaska Airlines
2h 42mSEA-DEN
9/16Sat
nonstopAlaska Airlines
2h 59mDEN-SEA
$157
9/2Sat
nonstopUnited Airlines
2h 16mGEG-DEN
9/6Wed
nonstopUnited Airlines
2h 23mDEN-GEG
$158
7/26Wed
nonstopMultiple Airlines
2h 45mSEA-DEN
8/2Wed
1 stopMultiple Airlines
5h 53mDEN-SEA
$161
7/1Sat
1 stopDelta
4h 35mGEG-DEN
7/14Fri
1 stopDelta
4h 34mDEN-GEG
$199
8/3Thu
1 stopAmerican Airlines
16h 41mGEG-COS
8/10Thu
2 stopsAmerican Airlines
23h 03mCOS-GEG
$298

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Recent one-way flight deals

7/12Wed
nonstopFrontier
2h 45mSEA-DEN
$51
9/23Sat
nonstopFrontier
2h 54mSEA-DEN
$54
7/15Sat
nonstopFrontier
2h 45mSEA-DEN
$60
9/7Thu
nonstopFrontier
2h 55mSEA-DEN
$61
7/15Sat
nonstopFrontier
2h 45mSEA-DEN
$63
8/24Thu
nonstopFrontier
2h 45mSEA-DEN
$64
7/13Thu
nonstopFrontier
2h 43mSEA-DEN
$65
9/20Wed
nonstopUnited Airlines
2h 16mGEG-DEN
$73
7/11Tue
nonstopDelta
2h 38mSEA-DEN
$77
8/8Tue
1 stopSpirit Airlines
16h 23mSEA-DEN
$81
7/5Wed
nonstopUnited Airlines
2h 41mSEA-DEN
$86
6/28Wed
nonstopUnited Airlines
2h 45mSEA-DEN
$89
6/27Tue
1 stopSpirit Airlines
16h 23mSEA-DEN
$90
7/14Fri
nonstopDelta
2h 38mSEA-DEN
$95
8/7Mon
nonstopDelta
2h 38mSEA-DEN
$98
7/7Fri
1 stopAmerican Airlines
5h 31mSEA-DEN
$99
9/23Sat
1 stopSpirit Airlines
5h 13mSEA-DEN
$100
7/31Mon
1 stopMultiple Airlines
21h 30mBLI-DEN
$102
7/23Sun
1 stopMultiple Airlines
26h 14mGEG-DEN
$115
9/25Mon
1 stopAlaska Airlines
6h 12mGEG-DEN
$159

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Flights to Colorado

Return flight deals:

Colorado - Washington

Cabin classes:

$429
$641
$458
$103

Browse origins:

$199
$737
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