$70 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 4/24. 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
$217
Overall average: $355
Alaska Airlines
Sat 4/25Wed 4/29
SEA - STL • Non-stop
Cheapest one-way
$70
Typical prices: $184-$293
Frontier
Fri 4/24
SEA - STL • 1 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

Sat, Apr 25 - Wed, Apr 29
Alaska Airlines Logo
5:57 pm - 11:59 pm
SEA
-
STL
4h 02mnonstop
Alaska Airlines Logo
7:00 am - 9:32 am
STL
-
SEA
4h 32mnonstop
$217Alaska Airlines
Thu, May 7 - Fri, May 15
Frontier Logo
4:20 pm - 7:12 pm
SEA
-
STL
24h 52m
1 stop
Frontier Logo
8:12 pm - 9:27 am
STL
-
SEA
15h 15m
1 stop
$219Frontier
Tue, Apr 21 - Sat, Apr 25
Southwest Logo
11:40 am - 11:15 pm
SEA
-
STL
9h 35m
2 stops
Southwest Logo
10:35 am - 5:55 pm
STL
-
SEA
9h 20m
2 stops
$220Southwest
Fri, Apr 17 - Mon, Apr 20
Frontier Logo
7:12 pm - 7:32 pm
SEA
-
STL
22h 20m
1 stop
Frontier Logo
8:17 pm - 9:27 am
STL
-
SEA
15h 10m
1 stop
$221Frontier
Mon, Apr 20 - Wed, Apr 29
Multiple Airlines Logo
4:20 pm - 11:19 pm
SEA
-
STL
28h 59m
2 stops
Multiple Airlines Logo
7:00 am - 9:32 am
STL
-
SEA
4h 32mnonstop
$223Multiple Airlines
Tue, Apr 14 - Wed, Apr 22
Southwest Logo
6:30 am - 5:55 pm
SEA
-
STL
9h 25m
2 stops
Southwest Logo
5:30 am - 6:00 pm
STL
-
SEA
14h 30m
2 stops
$225Southwest
Thu, Apr 16 - Sat, Apr 25
Frontier Logo
4:20 pm - 11:19 pm
SEA
-
STL
28h 59m
2 stops
Frontier Logo
8:17 pm - 9:27 am
STL
-
SEA
15h 10m
1 stop
$226Frontier
Wed, Apr 8 - Wed, Apr 22
Alaska Airlines Logo
6:02 pm - 11:59 pm
SEA
-
STL
3h 57mnonstop
Alaska Airlines Logo
7:00 am - 9:32 am
STL
-
SEA
4h 32mnonstop
$227Alaska Airlines
Mon, Apr 13 - Thu, Apr 23
Southwest Logo
11:55 pm - 9:30 am
SEA
-
STL
7h 35m
1 stop
Southwest Logo
7:20 pm - 12:40 am
STL
-
SEA
7h 20m
1 stop
$229Southwest
Fri, May 1 - Wed, May 6
Frontier Logo
7:12 pm - 7:32 pm
SEA
-
STL
22h 20m
1 stop
Frontier Logo
6:51 pm - 10:22 am
STL
-
SEA
17h 31m
1 stop
$231Frontier
Useful Info

Good to know

Low seasonJanuary
Cheapest flight$70
Best time to beat the crowds with an average 35% drop in price.
Most popular time to fly with an average 10% 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 54m.

  • How many flights are there between Seattle and Belleville?

    8 direct flights run between Seattle and Belleville on a daily basis. On average, there are about 56 departures each week.

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

    Consider leaving on a Tuesday and avoid Sundays 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 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 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
Alaska AirlinesOverall score based on 12042 reviews
7.8Comfort
7.1Food
8.5Crew
8.1Boarding
7.0Entertainment
Airline reviews

The crew inside the airport for Alaska was rude, lazy and incompetent

10.0 ExcellentAnonymous, Mar 2026
SEA - BZN
Read more Alaska Airlines reviews

The crew inside the airport for Alaska was rude, lazy and incompetent

The flight was extremely smooth, and so was the landing. Great piloting.

Plane was clean, staff was professional and flight was on time. No built in tv was still ok, as programs were offered that could synch to smart phones.

J was in the ER x 3...3 protruding discs...contacted Alaska many many days prior to cancel and request a refund or a credjt.. they only gave me 50 % credit....outrageous seeing how i have a doctors letter....just plain inhuman. AI sucks!

The flight was too short. No snacks or drinks offered.

The flight attendant was friendly and attentive. Although our interaction was brief—- it made a difference. The crew was upfront about turbulence. I like the Maui pretzels.

Everything was good. Please have a wheat free option for snacks in the future.

They are always so great! Friendly, on time if not early, organized boarding process. Great price too.

Crew very courteous. Boarding was great. Slow to get baggage at Denver.

Lester and the rest of the crew were such a joy. Also, I want to thank the pilots for getting us there on time, and safely. My first amd only choice will always be Alaska Airlines.

Long layover between flights to Long Island from BWI - need better coordination between flights

I elected to pay for the upgrades and found very little difference

The new seating arrangement is so over priced for what you get.

The problem with the seat assignments is that there were a lot of rows in the front that were empty but my row at the back was full. Just not so pleasant.

No food or entertainment, just a quick 40 minute flight. A little bumpy due to Santa Ana winds but pilot has no control over that. Good flight and landing!

Good but I prefer choose your own seat. With the new assigned seats they should board from the back I see no advantage to this new boarding. Just like every other airline

I realize they are still working out kinks with the new boarding process, but by the time I boarded in group 5, most of the bins were full. All airlines should better enforce small bags and jackets going under the seats until everyone has boarded.

WiFi was not working and didn’t have a beverage service

Snacks are always pretzels. Why can't you also offer peanuts ?

Flight boarded late after announcing on time boarding. Flight arrived only a little late despite late departure. Had trouble connecting to WiFi

We landed and sat on the tarmac for 45 minutes because they only have one gate at the airport and there was another plane running late so we had to wait

The WiFi was not working. That made for a long flight.

Absolutely no communication on why there's a delay and multiple flight time reschedules. I would have canceled the flight and drove back home if I known it was going to be rescheduled 3 or 4 times.

Another late night flight and MORE men belligerently drinking and yelling. I had to move from first to economy because they were so obnoxious and disruptive. Crazy to go from a cozy chair to cardboard when you were supposed to be in first. Delta allows was too much drinking which leads to belligerent behavior.

I was in first class and literally the men behind me were so aggressively loud I moved myself to economy. This has become so common on Delta - people using audio without headphones, and men on 12am / late night flights drinking and yelling to talk to each other which prevents anyone around them from resting. Pretty crazy to have to move from first to economy (poorer service, less comfort...). Wild wild. Looking into other airlines.

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

There was an unruly family behind us that made the short flight miserable!!! The cabin crew did nothing to contain it.

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

Flight delay was frustrating, also you cannot checkin online without delta app, web browser check-in throw errors

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

The crew were exceptionally nice and accommodating. My wife was tired after the flight from Haneda, Tokyo. They let her sleep and served her dinner later after she woke up, before we landed in PDX.

No charging outlets worked. Other than collecting trash attendants didn’t come around. No one could hear flight attendants announcements during the flight. Seat pads were horrible. Sitting on a board for 5 hours. What happened to Hawaiian airlines comfort, hospitality, and extras? Our pilots did an excellent job trying to minimize turbulence and incredible job in landing in windy conditions.

There was no wifi available at any price -- the plane did not have wifi equipment. Movie choices were blah - hits from the past; nothing recent. The food was blah airplane food. They should have had Mai Tai drinks available as per the Hawaiian Airlines magazine, but they had none onboard.

I like that if they asked you to checked in a bag at the gate they give you priority to board

Horrible food and crew. Crew were laughing and talking loud while people were trying to sleep

Yall need to integrate your system with Alaska more efficiently. They booted me off the first flight because of a discrepancy on your end.

The crew at Hawaiian Airlines was fantastic. Kind and hard working. The pilots were great with giving us all the updates to make sure we were informed.

Very good. Nice plane and we sat in economy plus - bigger seats, more room. They served a meal and snacks, and the meal was an apple stuffed pancake that was very good! The snack for us was a hummus sandwich - also very good. The flight attendants were helpful and nice. They have plenty of movies and shows to watch. My only negative -- they changed our flights around and did not adjust the layovers, so we ended up with a very long and unnecessary layover in Honolulu.

I liked the Starlink WiFi but didn't like how they said they were the only airline to offer a free meal and it turns out to be just a standalone sandwich and then charge for snacks to go with it. Rather have the free snacks like Southwest, but have the option to purchase a decent meal for a 5+ hour flight.

Flight scheduled to take off at 5.55pm but it did not take off until 7pm due to some food delivery delay.

There was no inflight service. Once we landed we were delayed to find a gate for an hour and a half which was 1/2 the total time in the air.

The chicken wrap was tiny ($13 for what looked like a 1/3 of a normal wrap?) and disgusting.

It was good experience this time. The flight was on time.

There was a delay with the plan which cause the flight to leave later and once arrived in Chicago there was another delay and some passengers missed their connecting flights

The gate agent had a really bad attitude and refused to help me get on the standby list. She just handed me a card and said I needed to call a number. I asked her to help with the AA app on my phone and she just shrugged and said she didnt know. After a few phone calls, I eventually just went to a different gate agent on the other side of the terminal and got the help I needed.

Overall, my last three trips on American Airlines have all been either delayed or "rescheduled" due to mechanical issues. At least on delay caused me to miss two possible connecting flights each later than the first. My last option for my last connection required the assistance of the onsite service desk (O'Hare Airport). The wait time for the service desk was such that it jeopardized getting booked on the last connecting flight available for the night. Suffice it to say, my latest experiences with American Airlines have caused me extensive loss of productive business and personal time and can therefore be classified as significantly less than satisfactory.

Waiting for gate in RDU for more than 20mins is crazy.

American Airlines was great and worked very hard to change my ticket so I could get an earlier, direct flight back to Dallas. However, I was informed that Kayak made mistakes with my itinerary and classified my ticket as desiring to be on the earlier flight instead of taking the necessary step of calling AA to get me on the standby list. This ended up keeping me from being added to the standby list and delayed me getting home by 6 hours. I am happy to discuss this further with Kayak so they can correct their procedures so this won't happen again.

Waited for oxygen tanks for 30 minutes after boarding was complete.

We flew in first class. The crew did not offer drinks before the flight took off, but they treated us well during the flight. The food was excellent. There was actually too much food served, but it was nice to have all the options.

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

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