$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 1/30. 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.
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1 adult, Economy, 0 bags

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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

Sun, Nov 23 - Thu, Nov 27
Southwest Logo
6:35 am - 3:05 pmSEA-STL
6h 30m1 stop
Southwest Logo
6:25 am - 10:55 amSTL-SEA
6h 30m1 stop
$237Southwest
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Thu, Nov 20 - Sun, Nov 23
Southwest Logo
7:05 am - 5:20 pmSEA-STL
8h 15m2 stops
Southwest Logo
2:30 pm - 8:00 pmSTL-SEA
7h 30m1 stop
$242Southwest
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Mon, Nov 17 - Thu, Nov 20
Delta Logo
11:10 pm - 9:46 amSEA-STL
8h 36m1 stop
Delta Logo
6:34 am - 12:56 pmSTL-SEA
8h 22m1 stop
$243Delta
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Fri, Nov 14 - Sun, Nov 16
Frontier Logo
11:43 am - 3:56 pmSEA-STL
26h 13m1 stop
Frontier Logo
7:02 pm - 10:55 amSTL-SEA
17h 53m2 stops
$246Frontier
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Wed, Dec 3 - Sun, Dec 7
Alaska Airlines Logo
8:34 am - 2:27 pmSEA-STL
3h 53mnonstop
Alaska Airlines Logo
3:23 pm - 5:59 pmSTL-SEA
4h 36mnonstop
$247Alaska Airlines
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Thu, Nov 13 - Mon, Nov 17
Frontier Logo
12:58 pm - 9:07 amSEA-STL
18h 09m1 stop
Frontier Logo
9:07 pm - 12:07 pmSTL-SEA
17h 00m2 stops
$249Frontier
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Thu, Dec 4 - Sun, Dec 7
Alaska Airlines Logo
6:05 pm - 11:59 pmSEA-STL
3h 54mnonstop
Alaska Airlines Logo
7:00 am - 9:40 amSTL-SEA
4h 40mnonstop
$257Alaska Airlines
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Mon, Dec 1 - Sat, Dec 6
American Airlines Logo
12:59 am - 12:37 pmSEA-STL
9h 38m1 stop
American Airlines Logo
11:35 am - 6:55 pmSTL-SEA
9h 20m1 stop
$262American Airlines
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Mon, Nov 17 - Thu, Nov 20
American Airlines Logo
12:41 am - 10:39 amSEA-STL
7h 58m1 stop
American Airlines Logo
7:00 am - 1:09 pmSTL-SEA
8h 09m1 stop
$269American Airlines
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Sun, Mar 1 - Tue, Mar 3
Delta Logo
9:55 am - 8:39 pmSEA-STL
8h 44m1 stop
Delta Logo
7:00 am - 12:26 pmSTL-SEA
7h 26m1 stop
$297Delta
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Everything you should know

Cheapest round-trip
$237
Overall average: $383
Southwest
Sun 11/23Thu 11/27
SEA - STL • 1 stop
Cheapest non-stop
$247
Typical prices: $340-$740
Alaska Airlines
Wed 12/3Sun 12/7
SEA - STL • Non-stop
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Belleville!
Useful Info

Good to know

Low seasonJanuary
Cheapest flight$63
Best time to beat the crowds with an average 14% drop in price.
Most popular time to fly and prices are also 11% lower on average.
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 AirlinesSEA-STLJul 2025
Give yourself extra time. Love the self check in options.
Verified travelerFlew with Alaska AirlinesSEA-STLFeb 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 52m.

  • How many flights are there between Seattle and Belleville?

    10 direct flights run between Seattle and Belleville on a daily basis. On average, there are about 70 departures each week.

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

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

  • 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 Frontier for $63. Southwest offered a round-trip connection from $237 and Delta from $243.

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 57 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 11214 reviews
7.1Food
8.5Crew
7.0Entertainment
8.1Boarding
7.8Comfort
Airline reviews

Its bumpy but I can say its safe flight ,Thanks Alaska airline for bringing me in my destination😊.

8.0 ExcellentMary Grace, Oct 2025SEA - BNA
Read more Alaska Airlines reviews

Its bumpy but I can say its safe flight ,Thanks Alaska airline for bringing me in my destination😊.

Almost 3 hr delay in Settle with very little information available to passengers. They boarded the plane and we waited for a long time inside the plane as well.

This was our first time flying with Alaska. It was a seamless experience, with comfortable seats and leg room. Staff were friendly and helpful.

Flight on time. Crew good. Seating Bad. Have to pay extra on a not cheap flight to avoid being next to toilet.

The crew was great! Passengers were nice. Just an fyi that I heard several of them complain that the snack was not gluten free. Many people got handed the snack and then promptly gave it back to the flight attendant. Might be good to look into another option as such a high percentage of people in CO and WA are gf. Cheers!

Food and entertainment not applicable - standard drinks and cinnamon cookies; crew did not do a song and dance for us so no entertainment. I like the slightly better leg room than American Airlines - at least it felt that way. Flight crew and atmosphere seemed more welcoming than American, too.

It was fine, mostly I was just happy to be on my last leg home. No in flight entertainment but that's forgivable since it was only a 2 hour flight.

Was delayed in Newark 24 hours due to mechanical problems. The staff was very helpful in trying to make the best of a trying situation. In SeaTac, they changed gates and times. Usually have no problems from SeaTac.

Flight was cancelled, then rebooked on a flight that I was unable to get through since they had closed the gate.

Terrible. We were bumped off our flight to another and weren't sent notice until we were on our prior flight. We got home four hours later and the airline couldn't have cared less.

Ever since Southwest starting charging for bags, passengers don't want to pay to check their bags, so the gate agents have to beg people to check their roller bags now because there's "not enough space". This was a terrible business move by Southwest.

Full cans of soda would be nice. A choice between two snacks would be appreciated.

Tried watching free movie and it kept freezing so I couldn’t finish.

All was good. I just had a hard time getting connected to the WiFi/internet during the flight

Sacrament staff are always polite and helpful. Airport is easy to maneuver and boarding is straightforward.

Great flight. Outstanding Service. Southwest was able to put us on a direct flight to Denver when the connection could have been affected by a later arrival to Baltimore. The direct flight was less expensive that the flight with the connection in Baltimore.

Delays delays delays. Late taking off, late landing, wait for a gate, etc.

Boarded on time but once we were ready for take off, the crew determined that, although every seat was taken, somehow someone was on the wrong flight. Delay, delay delay, announcements and ended up with one person checking EVERY ID against their passenger Manifest only to figure out it was a "clerical error." We departed 54 minutes late causing me to run in the St. Louis Airport to make my connection and lose the priority boarding spot I had paid for. Unnecessary delay.

I was re-booked onto another flight because my original flight was delayed and I would have missed my connector. I ended up in the “C” group after paying extra to be in the “A “ group on the original flight. At least if you’re going to re-book people, re-book them into the same group.

Flight was delayed due to plane not passing inspection And one of the crew had to time out and we had to wait for another one A 3 hour delay

Everything went well and was good. Nothing exceptional, but no complaints either. Cheap seats are pretty comfortable.

Staff were friendly and happy. Delta could make sure passengers that don't have the app know of changes. Without Kayak I would not have known about the change of gate or the delay. Kayak was faster to notify me.

They ended up paying for the bag twice, but the counter wouldn't take my baggage receipt. Left it to me to resolve. Not sure how to resolve the issue.

The customer service before board was very rude and when I expressed my concerns about making the connecting flight she laughed and told me I bought the wrong ticket. I explained once it showed the flight was delayed it no longer let me change seats or anything. I was trying to upgrade to make sure I would get to the next gate on time.

Non stop on long haul is the way to go. Great experience

The flight used a B767 with a very old interior from before 2014. The entertainment system did not work at all during the flight despite attempts to reset the system. It was like they flew this route just to be competitive.

They changed planes and the new plane couldn’t carry enough fuel to fly across the country so we had to stop in Kansas City to refuel. Flight was delayed .

Flight was too crowded and seats are too small, especially since passengrs are getting larger. Having a middle seat is ALWAYS tough! Woman on my left was large & kept creeping in to my space. Flight personnel were great! Have more savory rather than sweet snacks please.

Flight was crowded and the woman sitting on my left was large & kept crouching in to my space. You need bigger seats or smaller passengers to fit into the seats you DO have! Snack were OK. Would appreciate if airlines had more savory rather than sweet snacks, thank you!

Delayed flight (1hour) plus a long layover after an overnight flight with no backup plane available.

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!

I received several emails about my 3:10 flight. When I showed up to the airport at 12:30 to check my bags I was told the flight was actually at 1 pm. They grudgingly rebooked me for a flight at 5:22 to Vegas to get a connecting to LAX. I did find the gate for my original 3:10 flight but they were booked. I proceeded to receive status updates and gate change information for the 3:10 flight, even though I was apparently never supposed to be on that flight

My flight was delayed three hours and then cancelled. The gate agent proceeded to rebook me in a middle seat without telling me and I was placed between two large individuals who did not fit in their own seats and instead took up most of mine. It was an awful experience.

The food options were limited and very specific. Some type of entertainment option for a 4.5 hour flight would have been nice.

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.

Food was ok, but not as good as I have had before on AA.

Pretty good. The food was just mediocre, the boarding and crew were good.

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

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