$94 Find Cheap Flights from Seattle to Belleville - Compare and Save

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 8/26. 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
$293
Typical prices: $260-$466
Southwest
Mon 9/28Thu 10/1
SEA - STL • 2 stops
Cheapest non-stop
$337
Typical prices: $287-$553
Alaska Airlines
Tue 10/20Tue 10/27
SEA - STL • Non-stop
Arrival airport
You can't fly directly to Belleville. It is served by St. Louis (STL), located 26.3 miles from Belleville.
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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

Mon, Sep 28 - Thu, Oct 1
Southwest Logo
1:25 pm - 12:40 am
SEA
-
STL
9h 15m
2 stops
Southwest Logo
8:35 am - 6:10 pm
STL
-
SEA
11h 35m
1 stop
$293Southwest
Mon, Oct 5 - Thu, Oct 29
Southwest Logo
8:40 pm - 11:40 am
SEA
-
STL
13h 00m
1 stop
Southwest Logo
2:25 pm - 10:30 pm
STL
-
SEA
10h 05m
2 stops
$293Southwest
Sun, Aug 16 - Mon, Aug 24
Frontier Logo
8:53 pm - 6:15 pm
SEA
-
STL
19h 22m
1 stop
Frontier Logo
7:58 pm - 9:19 am
STL
-
SEA
15h 21m
1 stop
$294Frontier
Wed, Oct 7 - Tue, Oct 27
Frontier Logo
4:27 pm - 7:15 pm
SEA
-
STL
24h 48m
1 stop
Frontier Logo
10:35 am - 9:51 am
STL
-
SEA
25h 16m
2 stops
$295Frontier
Wed, Nov 18 - Wed, Dec 2
American Airlines Logo
6:12 am - 4:43 pm
SEA
-
STL
8h 31m
1 stop
American Airlines Logo
9:30 am - 2:55 pm
STL
-
SEA
7h 25m
1 stop
$307American Airlines
Fri, Oct 2 - Sat, Oct 10
Multiple Airlines Logo
9:45 pm - 11:32 am
SEA
-
STL
11h 47m
1 stop
Multiple Airlines Logo
6:02 am - 8:33 am
STL
-
SEA
4h 31mnonstop
$318Multiple Airlines
Mon, Oct 5 - Tue, Oct 27
Multiple Airlines Logo
9:45 pm - 11:32 am
SEA
-
STL
11h 47m
1 stop
Multiple Airlines Logo
7:02 am - 9:35 am
STL
-
SEA
4h 33mnonstop
$318Multiple Airlines
Tue, Aug 18 - Wed, Aug 26
Delta Logo
11:10 pm - 9:37 am
SEA
-
STL
8h 27m
1 stop
Delta Logo
8:48 am - 1:00 pm
STL
-
SEA
6h 12m
1 stop
$333Delta
Tue, Aug 18 - Sat, Aug 29
Delta Logo
11:10 pm - 9:37 am
SEA
-
STL
8h 27m
1 stop
Delta Logo
5:00 pm - 10:05 pm
STL
-
SEA
7h 05m
1 stop
$333Delta
Wed, Sep 16 - Mon, Sep 21
American Airlines Logo
12:35 pm - 6:38 pm
SEA
-
STL
4h 03mnonstop
American Airlines Logo
5:00 am - 10:09 am
STL
-
SEA
7h 09m
1 stop
$352American Airlines
Useful Info

Good to know

Low season

January

Cheapest flight

$94
Best time to beat the crowds with an average 42% drop in price.
Most popular time to fly with an average 4% 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 50m.

  • How many flights are there between Seattle and Belleville?

    13 direct flights run between Seattle and Belleville on a daily basis. On average, there are about 94 departures each week.

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

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

  • 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 5 days, 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 $104 and Frontier from $137.

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 77 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 January.

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
SouthwestOverall score based on 4228 reviews
7.5Entertainment
7.0Food
8.1Boarding
8.6Crew
8.0Comfort
Airline reviews

Flight was delayed over 3 hours. Planes were dirty. Staff indifferent. And they serve vegan pretzels as snacks.

2.0 MediocreMatthew, Jun 2026
CVG - MDW
Read more Southwest reviews

Flight was delayed over 3 hours. Planes were dirty. Staff indifferent. And they serve vegan pretzels as snacks.

The flight was smooth. The Southwest experience has degraded overall, but this one was okay.

The checking experience in Orlando was terrible, almost missed the flight. Too many travelers and Southwest completely understaffed.

Not having a five hour delay with little notice! The crew was very kind, though, and just as tired as we passengers were. The flight didn't depart until nearly 1 am...and no reason was ever given.

no service at all due to turbulence. they should've at least given us snacks, there were only 10 people on the entire flight.

For the first time in a long time, the Wi-Fi actually worked the entire flight! The flight crew was amazing as usual.

Great flight from Seattle to Phoenix and to Chicago-Midway from Phoenix

I really like open seating. I hate that I've heard this is going away. This is one of the unique things that makes Southwest my goto choice.

The people of SW Airlines really make it nice to fly.

More assistance and clarity for travelers with gate checking and lap children

The flight kept getting delayed due to a maintenance issue. That happens, but there is no excuse for changing the gate FIVE TIMES, including one time nearly all the way across SeaTac. After we were delayed for 3+ hours, they did send us (via email) a $12 meal voucher...except you can't find a $12 meal anywhere in that airport, unless you consider a bag of M&M's and a bottle of water a meal. The plane had one problem after another but finally took off 4.5 hours late. This caused us to miss our hotel shuttle at ORD (they didn't run past midnight and it was 3 am) so we had to wait 25 minutes and pay for an Uber. I did get a $50 flight voucher from Alaska...big deal. Barely covers my Uber ride that I shouldn't have needed.

Why was I charged for a glass of wine on one flight and not on another? Why no movie or TVs? It was a long flight.

Way too warm for that length of flight!! If the pretzel bag gets any smaller, there won't even be any pretzels to eat!! Crew didn't talk. $99 just for an aisle seat is ludicrous!! Probably won't fly Alaska again.

I had wonderful flight. Only negative was the entertainment. Because there was not any entertainment on the plane.

Great airline great seats a ;ittle turbulence but piolot handled it well

No issues with flight. A small delay due to waiting for aircraft but a non-issue. To me a good rating on a flying day is a good thing.

I appreciated the first class section not being overly expensive. I didn't appreciate the flight attendants discussing their concern with a mom and a crying baby (it happens!) with passengers like myself being able to hear their conversation. I know the area is tight but speak in code or something to be more professional and respectful of passengers. One of my worst fears in taking my children on a plane when they were younger was having a crying baby/toddler. It never happened but it caused me anxiety and I think a lot of women especially feel this. The food was good and flight was delayed two hoursdue to an issue with the baggage equipment at the Seattle airport.

It was warm on the plane. Perhaps the people who were coughing quite often should be encouraged to wear a mask?! It was a long 4 hours.

I usually choose Alaska Airlines over any other airline. They try the hardest to make flying a great experience.

Staff being friendly would have help since the flight was delayed, again. Folks answered questions but no one seemed happy to be working today and if showed.

My flight was delayed by 4 hours in 30 minute increments. The gate agents were amazing but the communication was not. We were told that there was a maintenance issue but they didn't know what it was. That didn't inspire confidence. Then they said they found it and it was fixed and the pilot just needed to sign off. Then the pilot needed to talk to the other pilot from the arriving flight and we'd be fine. Then we were waiting for the pilot to call back. Then the maintenance issue wasn't fixed. Then they decided we were getting a new plane (why didn't they decide this earlier??). Fine. But then they announced we were changing gates AND terminals. And we were boarding in 20 minutes. So we all had to run to the new terminal gate. We could have taken off at that time, but we then had to wait for all the people who rebooked on a different flight to book this flight again. That took 30+ minutes because there was only one gate agent. When everyone ditched this flight, I saw it as an opportunity to upgrade to comfort. Delta, the greedy jerks they are, charged me $121. After their delay, their fault, their issues, couldn't even discount an upgrade. They only handed out $12 meal vouchers for the delay. I can't even get a snack from starbucks for that.

Love me some Delta. One of the few airlines to recognize and support veterans. Easy boarding, flight was on time and arrived early and the flight attendants were excellent on this flight.

We sat on the runway for over an hour before departure. That was unwelcome.

Crew was nice, meal was good. Entertainment had to be rebooted 3 times and still did not work. Turns out there was residue on screen, it needed to be cleaned to prevent the touchscreen buttons from continuously activating. I had entertainment for the last 45 minutes of a 5 hour 45 minute flight. Really unacceptable for first class. Flight attendent indicated your cleaning solution creates this problem. Seems as if this is widely known, you should be using a different product or cleaning better. Really really disappointing which simply added to the wi fi on your planes with reliably never ever works.

Snacks and included beverages were appreciated. Boarding went smoothly. Plenty of overhead bin space. Seats get very uncomfortable after a couple of hours. After waiting 10 painful minutes for my walker, a very nice Delta guest agent pushed me in a wheelchair to the gate. It was finally delivered to me after another 15 minutes . Our checked bag was on the carousel long b4 I was able to retrieve it. Fortunately it was still there but somewhere along the way the straps we used to secure it were removed and and were not reattached. Wish I had made note of the agents name.

The cabin temperature was nice and cool. The wifi was not working.

Could not get my connecting flight boarding pass until four hrs before departure! Ver annoying especially since the staff could not explain why!

First flight out and was 85 minutes delayed. Notification came out way too late

Was forced to check in my small carry on, even though I informed the crew it has very fragile items inside

The staff did not do a good job of getting everyone boarded quickly, so we missed our take off window and had to sit on the tarmac for 20+ min waiting for our turn. The plan was old. Pockets on the back of seats were torn and tearing off. One of the attendants was rude-she would ask a question but he walking away before you finished answering so she kept getting our drink orders wrong.

Flight be on time would be a good start. Then train your flight attendants to be attentive and friendly. This time they completely forgot my row for the measly snack! United, do better!

Our flight was delayed several Times due to mechanical issues. Although I understand this may happen at times, it was very inconvenient and we had to book a hotel for an overnight stay. We were traveling with my 3-yo grandson and waiting at the airport from noon until 6:30pm with no reassurance that our next rescheduled flight would depart, we had to decide what’s best for him. A day later, I found out that I may be able to demand compensation if my flight is delayed more than 4 hours. I will hav to read the fine print next time.

United needs to step up their game. Delayed flight leaving Seattle, San Francisco. Older aircraft, not very comfortable.

Had to cancel first flight because Airporter Bus took over 3 hrs to get to airport which resulted in an extra $378 dollar fare . Is there anyway I can be reimbursed for initial fare since it was not my fault? Sent from my iPhone EJ Ledet

Delayed by 2.5hrs any longer and they would’ve had to honour their own policy for breaking their own rules and regs. Not cool, especially when I have an infant child that needs to stay on a routine and they get schedules.

They had three choices for snacks - but you could only have one - and they ran out of the dark chocolate before they made it all the way down the aisle... Packed flight - limited service.

They opened my checked bag and even though my lock was tsa approved, they loose my lock and left my bag just like that. Incompetent people, very upset about it. I’ll try to avoid traveling with united

We fly to Ecuador frequently. Checking in is usually a hassle because most United agents take some time before they can verify that my passport doesn't require a visa to Ecuador. This time the process was even longer due to the cyber attack. But she was really nice to us. So glad we brought plenty of snacks to supplement the 3 flights from SEA to GYE.

We had selected seats in the app that were a 2x2 format in the middle of the plane. Our seats when we got on the plane had been moved to the back rows in a 3x1 format. What’s the point of paying up for tickets that allow seat selection if the airline will just change them?

The new Airbus A231neo has neat tech but the economy seats are so tight together that I always had my shoulders against one passenger or the other. I was very miffed that Basic Economy REQUIRES check-in of bags other than your personal carry-on; if you want to offer low-cost airline prices and then add services for a fee, just let me carry on my duffel. Hell, I could have put my carry on IN the duffel and called it a day but the gate agent would not let me; I ended up paying $40 for the risk of losing my bag. Not the worst flight, but far from the best.

Flight attendants and crew were great! This plane was fine. It was clean and everything worked properly. Now, the gate change was not communicated. No text or information. It wasn't far with the gate change but it still changed without any communication. Not sure if this is on American or Kayakl. Also, internet was the worst. I would never have ATT. 3+hr flight and weak internet. I think I watched the commercials to get on at least 6 times. Terrible internet!

So excited very proud first of all I wanna thank kayak all updates very professional and fast alart And amazing cabin crew so nice to me they deserve big salute

Great flight - friendly and attentive team! Seats in coach were comfy, but a little cramped - but that is the case with all airlines ;)

Dreadful experience. Our flight was delayed more than 8 hours due to a maintenance issue and the assistance from rebooking was poor. I was travelling with a bad knee and needed assistance waited in one place more than 3 hours before someone came with a wheelchair. The woman next to me was a 91 year old great grandmother who had waited more than 4 hours. There were moments of support from the staff but it appeared as they were going against the direction of management. It was apathy, lack of ownership and dismissive responses with small moments of kindness and understanding typically from grey haired, female, veteran staff..

The only thing is if Wi-Fi is available after you land and taxi to the gate. It takes forever to get to the gate, and having the Wi-Fi continue would be great to bide the time at least 5 minutes before you arrive at the entrance. That is my only comment; otherwise, everything was good.

Airplane was cold. Flight attendants were rude. Phone charger did not work. No food available.

This flight was fine but had no time to breathe as the connection was late from Sea to ORD.. Super stressful. If we checked bags, the trip would have been very distressed.

Late and next flight even later. Who leaves at 245 am and arrives at 330 am ? No wifi, 4 hr flight and one bag of pretzels? AA should be ashamed

No problems on this flight. Entertainment system worked well. On time take off and arrival. Smooth most of the way.

Those seats were way too narrow. I had the middle seat, one person was a very skinny person and we still couldn’t avoid touching each other anytime one of us moved. The other person was larger and we were basically sitting in each others lap the entire flight. There was zero entertainment. The flight was long enough to justify tvs, but no. Gotta sit there in your infant seat and twiddle your thumbs.

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

Complete your trip to Belleville with a hotel stay or car rental