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Planning a trip from Seattle to Denver? KAYAK’s data-powered insights will help you find cheap flights. Learn the best time to fly, how early to book your ticket, and other tips to secure great prices.
The most affordable time to fly from Seattle to Denver is typically on a Tuesday or Wednesday, with January being the cheapest month overall.
Booking Advance: Purchase tickets at least 15 days in advance for the best rates.
Cheapest Airline: Frontier Airlines generally offers the lowest fares on this route.
Direct Flights: Direct flights, particularly with Frontier, are usually cheaper than those with layovers.
Route Selection: The route from Seattle/Tacoma Intl to Denver Intl is the most cost-effective option.
This feature is powered by ChatGPT: an OpenAI-developed artificial intelligence model trained with KAYAK proprietary data and third-party data not verified by KAYAK.
Low season | January |
---|---|
High season | July |
Cheapest flight | $38 |
Direct departures
Seattle/Tacoma Intl to Denver Intl
Monday
ANA, Air France, Air Tahiti Nui, +19 more
ANA, Air France, +20 more
18
19
Tuesday
ANA, Air France, Air Tahiti Nui, +16 more
ANA, Air France, +17 more
15
16
Wednesday
ANA, Air France, Air Tahiti Nui, +19 more
ANA, Air France, +20 more
18
19
Thursday
ANA, Air France, Air Tahiti Nui, +18 more
ANA, Air France, +19 more
17
18
Friday
ANA, Air France, Air Tahiti Nui, +19 more
ANA, Air France, +20 more
18
19
Saturday
ANA, Air France, Air Tahiti Nui, +18 more
ANA, Air France, +19 more
17
18
Sunday
ANA, Air France, Air Tahiti Nui, +19 more
ANA, Air France, +20 more
18
19
Direct returns
Denver Intl to Seattle/Tacoma Intl
Monday
ANA, Air France, Air Tahiti Nui, +19 more
ANA, Air France, +20 more
18
19
Tuesday
ANA, Air France, Air Tahiti Nui, +14 more
ANA, Air France, +15 more
13
14
Wednesday
ANA, Air France, Air Tahiti Nui, +19 more
ANA, Air France, +20 more
18
19
Thursday
ANA, Air Tahiti Nui, Alaska Airlines, +17 more
ANA, Air Tahiti Nui, +18 more
16
17
Friday
ANA, Air France, Air Tahiti Nui, +18 more
ANA, Air France, +19 more
17
18
Saturday
ANA, Air France, Air Tahiti Nui, +17 more
ANA, Air France, +18 more
16
17
Sunday
ANA, Air France, Air Tahiti Nui, +18 more
ANA, Air France, +19 more
17
18
Wifi would be nice. Unfortunately the particular airplane was not equipped with wifi.
Wifi would be nice. Unfortunately the particular airplane was not equipped with wifi.
I'm so glad that Alaska still keeps this little "puddle-jumper" route going between SEA>ALW; my daughter lives on Walla Walla, and it's so much quicker to be able to fly right in to Walla Walla than to have to fly into Tri-Cities and then make her drive 40 minutes each way. This flight is usually only 50%-75% full when I fly it, but that's because it doesn't get in to ALW until MIDNIGHT! But thanks for continuing to service the Walla Walla area, Alaska!
Seats very comfortable and legroom appreciated. All in all, it was a great experience.
Original flight was canceled, and the automatically booked second flight was immediately delayed. I arrived about 4 hours later than planned with only a $12 meal voucher that didn't fully cover a sandwich at airport prices.
I was expecting better service from Alaska Airlines. I registered for assistance since I have a disability. The terminal in Seattle, WA was very unprofessional and at times rude. The BWI location was the exact opposite. I will NOT consider Alaska Airlines for future flights.
It was very good and comfortable, Crew was also great
The flight was delayed almost an hour. No wifi on flight.
Good experience, although it was a little cramped being a tall person. Otherwise everything went smoothly and professionally though
We have always flown with Alaska when we can. As they have great customer service. This trip we had to transfer to Air LINGUS in Denver to go to Dublin. That’s where things went bad! Our checked luggage didn’t arrive. The process to make a claim was way more complicated than it should be. It took 5 days to recover our luggage. The whole time we couldn’t talk to a real person who could tell us anything. The whole time Alaska blamed Air lingus and vis a versa. No one seemed want to help us. That was the worst part.
Delay of more than 3 hours I didnt recieve neither a voucher for food Attention disaster
It was one and half hour late... Not sure if any other experience matters.
Delayed flight. Nicest crew member was a SW pilot flying seated next to me who kindly move to seat the final passenger. Flight extra delayed. My cup of refreshment of ginger ale was so packed with ice it was literally 2 sips.
For my birthday trip this was my second time ever flying, this trip was the best.
after landing, we stay 2 hours on the taxi way before reaching the gate The airline and the crew were good though
No trays in our seats, we sat in first row, purchased a business class fare. Had to hold our drinks and snack in our hands. No plugs for our cell phones. Had to pay for it a drink cocktail each. Seats so uncomfortable.
Flight wasn’t even full, but too many carry-ons caused us to run out of bin space. New bag fee has folks who would usually check their bags carrying on. Watching Southwest morph into Spirit/Frontier is so sad to watch
Sat on tarmac for 2 hours and then missed my connecting flight
First time traveling on Southwest since bag fees were implemented. Usual good service. Just more expensive now.
Flights delayed by 4-6 hours. Boarding was a mess and unclear. Bags were not at arrival airport and had never even been put on the plane. No idea when I’ll get them. Don’t fly into Denver!
Southwest is typically delayed, and it gets wearisome. It is no longer a discount airline and you get way less than you pay for when it comes to comfort and Ce.
Everything was fine except the entertainment was not working for half of the flight.
Easy boarding with an extremely kind attendant. Seats were spacious and we had 3 seats for 2 people so we could stretch out. Comfortable air flow and very attentive and hospital attendants. Bathrooms and food were the only negative. Bathrooms were so small you could hardly get in and close the door. I don’t think an obese person would fit or a person with a movement disability. Food was the trending food for flights, nonexistent. We spent $40 getting sandwich and snack at airport for our 6 hour flught.
At first, we were on the runway for about an hour, literally. The Captain did explain that the Control Tower just had a change shift (sounds like an unrealistic excuse) and then that we had to change a runway. A regular economy seat is made for 12 yo twiggy. I understand Delta wants to push for an upgrade, but after sitting in a Comfort seat and in First class. I would say First class is not worthy of my money. The landing was delayed because of the weather in NYC, I don't hold that against Delta, of course. The Captain did alert us to that upon takeoff in Vegas and again as we reached NY.
No one fussed at me about my pap machine as a 3rd pice on the plane. Boarding was pleasant and smooth. The boarding agent in Anchorage was a fun character- he could be in a movie. :~) The on-board crew were downright pleasant. No militant attitudes on Delta. Like all planes these days the seats are too narrow for standard Americans and at 5’2” there is barely enough leg room. I don’t know how tall people fold themselves into the seats. But that’s nothing specific to Delta
My husband upgraded our seats and I don't know if it was due to the type of planet was or if they didn't upgrade our seats. We were supposed to be in I believe comfort seats and they were just as tight as any other seat- no leg room and we are very tall people but at least it wasn't extremely cold. My husband did put in a complaint about our seating because he paid extra and if we would have known that the space and the tightness would have been the same, we just would have gotten the emergency row emergency row seats that we normally get. We love Delta but both our flights coming home we're not good. Oh I forgot to mention that on our flight to Hawaii our luggage wheels got broke and we had to purse new luggage on vacation then we never had this problem so we didn't know protocol and reported it after we got home only for them to tell is we only had 24hrs to report the damage. Not sure what was going on with Delta this vacation trip.
My flight was extremely cold. I had a jacket and a cover was left in each seat. The cover was extremely thin and I have a disability, fibromyalgia and arthrithis and AC air is the worst. I closed my vent and my husbands vent and it still was frigid. I asked the attendant if I could get another cover and she quickly almost dismissively and totally unconcerned stating, (I quote) (one per chair) and walked off so quickly that I didn't get a chance to explain to her that I literally have adisability. I didnt want to make a seen so I set on that flight for over 5 hours in pain, joints locking up and extremely uncomfortable. When my fibromyalgia flares up my joints not only ache but they will lock up also and it takes me days to get back to my regular self even though I take medication for it. I felt like it would not have hurt anyone at all for her to just give me an extra cover because I'm sure they have all types of medical issues in people that fly every day.
After all the weather issues at least they got me to my destination the next day
My flight was canceled after being rescheduled for four days canceling my trip. Kayak and everyone affiliated with it I.e the airlines, and just fly have been excruciating to deal with. My trip to visit family had to be canceled as there was no way to make it. I am furious at all of you.
They delayed our flight because of bad weather in NY which was completely understandable. Then they cancelled our flight and a later flight that evening. The earliest we could fly was the next morning. We ended up buying last minute tickets on another airline and made it home slightly delayed but safely that evening. Delta kept saying it was weather related but if that was the case how did we make it back on another airline? The weather in NY was cloudy but not bad.
From Atlanta to Savannah - flight connection was way to short (we weren't even late landing ) and flight was already boarding when we landed - we were told we were the last on board and so we had to gate check our bags. Once we got on the plane, there were at least seven open bag spots so that was unnecessary delay. There should be better communication between the gate agent and the crew.
Very rough getting into denver. my kid threw up it was so rough.
Why wasn't this flight departure scheduled eith another crew so that it could leave on time? When we arrived in Denver we had so little time between flights we had run to the connecting flight. We should received some credit for the inconvenience.
I was supposed to be on business class at first class from Denver back to Miami due to weather changes. I missed my connection and it’s put on a flight to Fort Lauderdale. Instead of honoring my business class/1st class ticket, they put me in coach, but there were two first class seats open. I think it’s absolutely disgusting that I paid for first class $1300 ticket and they put me in economy and they had to open seats available and I have still not been refunded the difference. I ended up having to eat a snack box instead of the meal I was supposed to get and did not get home till 2 AM so I think that’s a little pathetic that I had to live off crackers for dinner And my poor dog ate some cheese and salami. Oh yes, apparently when they switched me to the new flight they forgot to mention I had a service dog
Excellent service despite turbulence during the flight. Flight attendants were remarkable!
Flight attendant moved my bag without notifying me and was rude to me when I asked him about it. There was no reason to move it.
Food choices were very limited. Taste of the dishes was average.
I liked all the informational texts. I always knew where to go and when .
Received an email the night before showing that there would be seatback entertainment on our flight. We get on and there was no seatback entertainment. And then it was a scramble to try to set up the iPads for the kids before takeoff so they could watch something for the four hour flight.
The reason I don’t fly United. No in seat entertainment for a long flight and inconsistent WiFi and entertainment available from my device.
It was a good flight. Nothing comes to mind about how it could have been better. It was a newer plane, seemed like a great upgrade from your older ones. Staff was very good as well.
My tickets got canceled on me by your site and I didn't have a flight. Then you kept sending me emails on the status of q flight I didn't have tickets for.
Flight was late. Missed connecting in Denver. My new flight is more than 24 hours later and I have no room, vouchers, or compensation, and might also be bumped from the one tomorrow.
This was one of the first frontier airline flights this spring that wasn't delayed. It actually left on time. Some of the flight crew did not look happy, they didn't smile when the passengers were boarding or getting off the plane, and the passengers initiated greetings, not the staff. To me this was an odd experience to have with any flight/airline. I had a bad experience booking this flight. The price didn't solidify until late hours into the night. Ever time I purchased the ticket, I either received a denial email or an error because the price has changed, but it was never reflected on the flyfrontier or kayak websites until way after midnight on the date of travel. This caused me anxiety and irritation with the websites. Then I noticed a mishap with my name on my voucher as I went to check in, it was incorrect. When I proceeded to correct it, Frontier had no easy, let alone free, way to remedy it. I couldn't correct my name without a $75 charge, I couldn't cancel my voucher to repurchase it with the correct name without a $100 charge, because it was too close to departure. Then calling frontier was nearly impossible to remedy the situation with a human. It's already difficult to want to choose frontier because of all the upcharges, but you feel kinda trapped into doing so because it's the more affordable airline.
Our flight was cancelled. They could do nothing to help us get another flight that was timely. Because the first leg was cancelled we were unable to get to our connection. We had to book on an entirely different airline for today. So we spent more money, lost a day of vacation and will never fly Frontier again, so the 'we are sorry, here is $100 credit' is a joke since we won't be flying on Frontier.
I liked the turn-style feature at gate 209B at LAX. Very efficient process. The gate staff also made several, clearly directed announcements so I felt very informed.
Seats are uncomfortable but price is good. Guess I can put up with misery for four hours.
The plane failed preflight inspection, so we sat there for 90 mins while they tried to fix it. Ultimately, everything was remedied and we made our connecting flight; instead of a 2 hour layover at the airport, we spent it waiting on the plane.
I loked walking out on the tarmac to board and no first class. I didn't like that they have no snacks or onboard wifi to bide your time.
The seats were extremely hard and uncomfortable. It was disappointing even for a budget airline.
Delayed each time on a round trip with no significant weather interference. Updates to flight times came after the fact. 30 min behind in boarding and board and phone still show an on time departure. Some mysterious extra 300 miles that came so surprising they had to fuel while we were already on board?
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