$63 Find Cheap Flights from Seattle to Belleville

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Seattle to Belleville departing on 1/9. 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

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Everything you should know

Cheapest round-trip
$237
Overall average: $606
Alaska Airlines
jue. 1/1lun. 1/5
SEA - STL • Non-stop
Cheapest one-way
$63
Typical prices: $139-$259
Frontier
vie. 1/9
SEA - STL • 1 stop
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Flight Deals
Useful Info
Flight Deals

Cheap Flights from Seattle to Belleville (SEA-STL)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Seattle to Belleville 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 round-trip flight deals from Seattle to Belleville

jue., ene. 1 - lun., ene. 5
Alaska Airlines Logo
6:05 pm - 11:59 pm
SEA
-
STL
3h 54mnonstop
Alaska Airlines Logo
5:26 pm - 7:59 pm
STL
-
SEA
4h 33mnonstop
$237Alaska Airlines
vie., ene. 30 - lun., feb. 2
United Airlines Logo
9:00 am - 8:58 pm
SEA
-
STL
9h 58m2 stops
United Airlines Logo
4:35 pm - 10:59 pm
STL
-
SEA
8h 24m1 stop
$242United Airlines
vie., dic. 26 - mar., ene. 6
Delta Logo
5:25 am - 1:23 pm
SEA
-
STL
5h 58m1 stop
Delta Logo
5:00 pm - 11:22 pm
STL
-
SEA
8h 22m1 stop
$243Delta
dom., ene. 11 - vie., mar. 6
Multiple Airlines Logo
9:23 pm - 12:12 pm
SEA
-
STL
12h 49m1 stop
Multiple Airlines Logo
2:47 pm - 5:26 pm
STL
-
SEA
4h 39mnonstop
$255Multiple Airlines
lun., ene. 5 - mié., ene. 7
United Airlines Logo
1:55 pm - 10:22 pm
SEA
-
STL
6h 27m1 stop
United Airlines Logo
8:45 am - 6:27 pm
STL
-
SEA
11h 42m2 stops
$258United Airlines
vie., ene. 9 - lun., ene. 12
Multiple Airlines Logo
7:55 am - 1:54 pm
SEA
-
STL
3h 59mnonstop
Multiple Airlines Logo
1:07 pm - 7:47 pm
STL
-
SEA
8h 40m1 stop
$262Multiple Airlines
jue., ene. 1 - mar., ene. 6
American Airlines Logo
12:14 am - 8:35 am
SEA
-
STL
6h 21m1 stop
American Airlines Logo
9:25 am - 3:34 pm
STL
-
SEA
8h 09m1 stop
$263American Airlines
mar., ene. 27 - mié., feb. 4
Southwest Logo
5:15 am - 5:10 pm
SEA
-
STL
9h 55m2 stops
Southwest Logo
3:50 pm - 11:05 pm
STL
-
SEA
9h 15m2 stops
$267Southwest
vie., ene. 2 - mar., ene. 6
Alaska Airlines Logo
6:05 pm - 11:59 pm
SEA
-
STL
3h 54mnonstop
Alaska Airlines Logo
5:26 pm - 7:59 pm
STL
-
SEA
4h 33mnonstop
$269Alaska Airlines
jue., ene. 8 - jue., ene. 15
Multiple Airlines Logo
7:23 pm - 9:21 pm
SEA
-
STL
23h 58m1 stop
Multiple Airlines Logo
2:50 pm - 5:25 pm
STL
-
SEA
4h 35mnonstop
$271Multiple Airlines
Useful Info

Good to know

Low seasonJanuary
Cheapest flight$63
Best time to beat the crowds with an average 16% drop in price.
Most popular time to fly with an average 16% increase in price.
Flight from Seattle to St. Louis

When to book flights from Seattle to Belleville

Are your dates flexible? Find out the best times to travel from Seattle to Belleville based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price

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

Insights shared by verified travelers who flew the route from Seattle to Belleville 
Verified travelerFlew with Alaska Airlines
SEA
-
STL
Jul 2025
Give yourself extra time. Love the self check in options.
Verified travelerFlew with Alaska Airlines
SEA
-
STL
Feb 2024
Be sure to measure your wheels for carry on my luggage was the correct size but the wheels made it over so had to check my bag wasn't happy about that since you have to pay for checked should at least get one free.

FAQs for booking flights from Seattle to Belleville

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

    When flying out of Seattle you’ll be using Seattle/Tacoma Intl. Belleville does not have its own airport so you’ll be flying into nearby Lambert-St Louis airport, which is 26.3 mi away.

  • How long does a flight from Seattle to Belleville take?

    Direct flights cover the 1,704 miles separating Seattle and Belleville in about 3h 46m.

  • How many flights are there between Seattle and Belleville?

    12 direct flights run between Seattle and Belleville on a daily basis. On average, there are about 86 departures each week.

  • What’s the cheapest day of the week to fly between Seattle and Belleville?

    Consider leaving on a Friday and avoid Sundays if you are looking for the best rates. For your return to Seattle, you’ll find the best rates on Mondays and the most expensive ones on Saturdays.

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

    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 Seattle to Belleville.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Belleville from Seattle 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 Seattle to Belleville?

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

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

    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 Belleville from Seattle up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • Which airlines provide the cheapest flights from Seattle to Belleville?

    In the last 72 hours, the cheapest one-way ticket between Seattle and Belleville found on KAYAK was with United Airlines for $74. Delta offered a round-trip connection from $94 and Frontier from $136.

Top tips for finding cheap flights from Seattle to Belleville

  • There is no airport in Belleville. Instead, you’ll be flying into St. Louis Lambert Airport when flying between Seattle and Belleville.
  • The cheapest flight from Seattle to Belleville was found 67 days before departure, on average.
  • Book at least 2 weeks 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 September.

Reviews of the top 5 airlines serving Seattle to Belleville

 
Need help choosing which airline to fly with from Seattle to Belleville? 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.
8.0
Alaska AirlinesOverall score based on 11436 reviews
8.1Boarding
7.1Food
7.8Comfort
8.5Crew
7.0Entertainment
Airline reviews

There was no food or entertainment so quit asking about that! Everything else was fine.

10.0 ExcellentDeborah, Dec 2025
SEA - RDM
Read more Alaska Airlines reviews

There was no food or entertainment so quit asking about that! Everything else was fine.

I wasn’t assigned a seat until last minute even though I checked in 24 hours before the flight and was told I might not be able to get on the flight! The leg room and seat room in the flight was abysmal. The service both at boarding and on the flight was very mediocre and not particularly friendly.

Late boarding, older plane. Great flight, no issues. Very cold inside the plane.

The plane was old so the seats were very worn out. The seats were hard, uncomfortable, and caused me actual pain. The lights were too bright. The flight itself was fine.

1. Denial of Basic Needs (SEA): Upon arrival in Seattle, the wheelchair attendant refused my urgent request to use the restroom, insisting on scanning documents first. She eventually took me to a restroom but then abandoned me and my autistic son at an unstaffed, deserted gate for over four hours. When I called the accommodation line for help, I was told to "get someone's attention," which was impossible. My son, traumatized by the prospect of me yelling for help, was forced to wander the terminal to find assistance. 2. Revocation of Accommodations & Threats: At the gate, an agent stated I had no accommodations on file, despite my previous leg having them. When I showed the app (where my bulkhead seat was erased and replaced with Row 14), he denied the evidence. When I attempted to advocate for my immobilized leg, he threatened to "yank me from the flight" if I said one more word. He coerced me into agreeing that I was "asking for accommodations for the first time" before he would allow assistance, effectively forcing me to falsify the situation under duress. I complied only out of fear of being stranded in a strange city. 3. On-Board Negligence and Injury: Because my bulkhead seat was revoked, I was forced into Row 14. With my leg immobilized and unable to bend, it extended into the aisle. During boarding and the flight: 16 different passengers tripped over my injured leg. 6 rolled luggage bags were pulled over my injured leg. The Flight Attendant (FA) was one of the people who tripped and drove luggage over me. I reported the issue to the FA after 10 trips and 3 luggage impacts. He ignored me. He only addressed me later to ask me to move my immobilized leg for beverage service. I informed him again: "16 people have tripped, 6 luggage runovers, I cannot bend it." He provided no medical aid and no incident report. 4. Resolution and Trauma: Eventually, a different employee noticed my distress and my original paper boarding pass showing the correct bulkhead assignment. He asked me to move up. I broke down in tears, terrified that moving would cause the gate agent to remove me from the plane as threatened. We were eventually moved to the bulkhead, but the damage was done. My autistic son was traumatized by watching his mother be trampled and threatened. 5. Post-Flight: I called to report these injuries, but was disconnected after a 45-minute hold. I require a formal record of this injury and these violations.

Larger seats with a bit more room would be good! Thanks for all your hard work. I think we are all feeling a bit down these days economically and your positive attitudes, both from SJC to Seattle and from Seattle to Bozeman makes more of a difference than you can see! Thank you and Merry Christmas! I hope all your financial needs are met and that very good things come your way.

We flew economy, it was what I expected. The seats are too upright for me

I purchased a 1st class ticket and unfortunately the main flight attendant was not the best and seemed more interested in her phone than the passengers at times. Then the plane didn’t get restocked and the only snacks for this flight were pretzels. However I would like to say that the rest of the flight crew and ground crew at the airport we’re great, especially the people that wheeled me around the airport some and then the one getting me to the plane and the automated wheelchair that wheeled me through the airport.

Typical domestic flight. No entertainment. You have to use your own devices and provided entertainment didn’t work. Pretzels and water of flight over 4 hours is unacceptable. Meals should be provided on long flights. But it’s about the money and not customer service. You should just issue the bag of pretzels at the gate and water bottle in seat and just do away with flight attendants because they do nothing on domestic flights

Very good. Easy check in, attentive flight attendant, and on time departure/landing.

The boarding and seat assignment system no longer works for me, but I know it is being replaced. Otherwise, I am good with the overall experience.

The lead steward kept singing about "San Francisco" and hotel California---more annoying than humorous....needs work. Flight was smooth and on time.

Still a fan of open seating. Flight was on schedule and arrived on time. The 737 MAX is very comfortable.

Airline travel is always too cramped to really be pleasant, but the cabin crew on this flight did a pretty good job of making up for it by putting on some music during boarding and sprinkling a few funny remarks into the safety briefing and announcements, and just generally being friendly and helpful. It definitely reminded me of why I prefer the in-flight experience on Southwest!

No delays and arrived to destination 30 min early. Staff was super friendly.

San Diego airport is brand new, spacious, airy and very smooth checkin at SW baggage drop.

It was rough. The staff was unprofessional, the choice of on board drinks terrible, it was cramped in space at every airport, they always ran out of overhead bin space so they pressured people to check bags for free or we couldn’t leave on the plane— so I did check my bag to help, and they nearly lost my bag. My bag did not arrive on the luggage belt, another man on my flight and I had to waste our time going to the baggage office to search for our bags. I would only fly southwest again if it was my last choice. Also, my flights were consistently delayed over and over again— at one point they straight up told us we were waiting for the pilot to arrive.

Crew could have been friendlier, maybe I'm spoiled by SW crews. In flight wifi was good. Would be nice to have more food offerings on a 4 plus hour flight

Had to get off plane from prior flight even though I had to reboard same plane to continue to my final destination.

Everything a cheap airline should be at normal airline rates.

Original flight was cancelled and when i was rebooked by the airline, they couldn't seat me in the same type of seat as I had originally booked (went from window/aisle to middle/middle and one was a bulkhead seat, and other wasn't in the same class)

Lady Pilot was perfect in every way wheels up to wheels down communication, professionalism, excellent on time departure and on time arrival, excellent communication! Fantastic job with Superb attitude!!

The food is terrible. The staff is wonderful. Comfort is good.

Left on time, a bit delayed due to headwinds most of the trip.

I fly Delta all the time, have Platinum Medallion status. But this route seems to have major problems with delays and seems to never leave on time! Have only taken it twice in the last two weeks, and each time it had delays of more than 1 hour... very disappointed!!!!

Good seats in Main cabin, excellent service and excellent landing

My flight was cancelled with no explanation after I had already cleared security. I was given 4 options to rebook, only one being non-stop like I had paid for. I grabbed it. It was 4 plus hours later and then took off even later. Biggest complaint is that I booked early and had an aisle seat. They gave me a "window" seat in front of the exit row, so the seat did not decline. I weigh all of 103 #s and it was tight for me! For what I paid, I feel I was kind of ripped off. I think they should have given me the empty comfort seat for the inconvenience. There was no apology nor any explanation as to why the flight was cancelled. My guess is it benefitted Delta in some way.

Very smooth, on-time, and pleasantly uneventful flight. The team at the gate and on board were professional and genuinely courteous. The pilot kept us well updated throughout, and both takeoff and landing were steady and enjoyable without any drama. Just a good, solid flight. Thank you! 💗

Staff was exceptional! Everyone was kind, professional and friendly making the trip very pleasant. Thank you!

No lunch on a x-country flight scheduled for 10:50 am departure, arrived 5+ hrs later. That requires a black box label before you pay for the tickets. Worst, when I checked in online, it's specifically said that lunch was served on his flight for economy Plus passengers.

Unfortunately, I was put into the middle seat in the first row of premium seating. Sounds nice right? No! that is the worst seat in the plane. I wish I was in economy rather than be in that seat! There is no seat back pocket, no tray table, no charger. Nothing! so unless you're row mates are willing to let you share their basic amenities any flyer should have, you are stuck. It was the worst experience ever! And the flight attendant forgot to take my drink order. I felt like the forgotten flyer.

Delayed and cancelled flights were hard and very stressful, both ways!

The crew was quite good, they came by often with drinks or to collect trash. But what wasn't nice was the flight was over weigh and several people had to be rebooked. I was questioned whether I should have a seat when I was getting to it. The in-flight entertainment kept buffering and interrupting. And the route took the airplane through high winds which caused us a longer flight

Wasn’t on the flight due to Alaska cancellation…also after all the rerouting, I was going to be on a later flight that left SFO at 7:47pm, which meant an almost 6 hour layover. That same Hawaiian flight was delayed for another 2hours.

I had to cancel the flight because with a 3 hour delay for 'unexpected maintenance' in getting to LAX, I couldn't connect to an overseas flight that I had booked on Scandinavian Air.

The flight was CANCELED!!! Can’t get much more “poor” than that. I had to switch to American Airlines, add another layover and got home in Honolulu 4 hours later than I was supposed to be home. One bright spot was Josh with Alaska Airlines at SFO. He got me on a United Flight that got me home a few hours before I would have. Without him I would have gotten home almost 7 hours after my originally scheduled flight.

Canceled my flight within 24 hours, causing me arriving home midnight. Will never book Hawaiian airlines anymore

I like Hawaiian, it was great that they had good internet connection across the Pacific Ocean, thanks to Star Link satellites. The seating was comfortable, ( I was in economy ). Maybe I missed it, but I only got offered a beverage once. It was a nonstop flight KOA to SMF. I would take it again next time I go that way.

I always love flying Hawaii and I have nothing to add

Previously flown Hawaiian Airlines on similar routes, I found Alaska Airlines to be noticeably more comfortable. The seats on Alaska Airlines provided better support and cushioning, which made a significant difference on the long flight to the islands. When you’re spending 5-6 hours in the air, seat comfort really matters, and Alaska Airlines delivered where it counts. After comparing both carriers, I’ve decided to book with Alaska Airlines for all my future Hawaii trips. The superior seat comfort alone makes it worth choosing Alaska over Hawaiian Airlines. If you’re planning a trip to Hawaii and prioritizing comfort, I’d recommend giving Alaska Airlines a try. You won’t be disappointed. Highly recommended for Hawaii travel!

Awful. They won’t help me with anything. I booked on American but they abdicated to Iberia. The ticket was overpriced. Everything negative

I enjoyed the extra leg room compared to other airlines. The first stewards made my daughter’s birthday special by giving her an extra snack. Then the last one coming home from Chicago to Appleton made our night really enjoyable Thanks for making our trip enjoyable

It was good..clean, comfy seat. Friendly warm welcoming crew. Was able to check my cabin luggage at the gate which I was able to pickup in a decent time from baggage claim. The app gave all updates from delays to baggage claim info. Overall smooth flight.

It was a typical flight. We had a delay which seems to be the normality now. And we had no in flight service due to conditions.

After we landed we sat on the tarmac for 1.5 hours waiting to get to our gate. Ridiculous.

Terrible. Flight delayed for more than 8 hours with only a $12 meal voucher provided for the inconvenience. The airplane did not have breaks on arrival yet they still made us go through the motions and board on time knowing we could not take off then sit for 40+ minutes before having to get of the time. A complete waste of my time. I cannot believe they can stay business with these shenanigans. I’ll avoid this company like the plague moving forward as the lack of accountability is disgraceful.

This was the best 2 flights I have had with American out of SGF. Great crew both flights.

Excellent - explanations were clear staff was nice and flight was comfortable

Lost bag and 2 days no word leaving for cruise no clothes or stuff

Any flight to ORD after about 2pm this summer has been challenging. Flight was delayed getting in (coming from ORD) and that led to it not leaving before a ground stop due to lightening before they could fuel the plane, and so forth. They made up some time but we were still late in arriving at ORD, and that led to missed connections.

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

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