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Flights from Seattle to St. Louis

Hi, I've summed up all the key info for Seattle to St. Louis flights

Cheapest one-way

US$ 81
Delta Air Lines Fri, Oct 30

60% below next 30d avg. (US$203)

Cheapest round-trip

US$ 159
American Airlines Thu, Sep 24

67% below next 30d avg. (US$478)

When to fly

November Cheapest month
July Peak month

Fastest flight

3h 59m Avg: 3h 59m

Recommended airlines

With a lowest one-way fare of US$81 , travelers can expect an average price of US$203 for upcoming trips, while round-trip tickets start at US$159 . Flights typically take around 3h 59m , but the fastest nonstop option completes the journey in just 3h 59m minutes. There are 34 flights weekly on this route. You can land at any one of the following hubs in St. Louis: St. Louis Downtown Airport (CPS) , and St. Louis Lambert International Airport (STL) . Flying from Seattle-Tacoma International Airport to St. Louis Lambert International Airport (SEA-STL) is by far the most common option on this route. To secure the best rates, booking 40 days in advance is recommended, and the cheapest travel days are Tuesday, Wednesday, and Saturday .

Updated 2d ago · This content is an AI-powered summary based on Trip.com data. Prices and availability are subject to change. Please refer to actual prices, availability, and travel conditions.

Explore the cheapest one-way and round-trip flights from Seattle to St. Louis over the next 90 days, with one-way fares from US$81 and round-trip from US$159. Based on Trip.com's latest 7-day flight data.

      • Cheapest nonstop
        SEA 12:35
        4h 3m
        Nonstop
        STL 18:38
        Seattle - St. Louis | Thu, Sep 24 | Alaska Airlines
        STL 10:55
        4h 20m
        Nonstop
        SEA 13:15
        St. Louis - Seattle | Mon, Sep 28 |
        US$246 US$348
        28% off
        28% off
        US$348 US$246
      • SEA 18:03
        3h 56m
        Nonstop
        STL 23:59
        Seattle - St. Louis | Mon, Sep 21 | Alaska Airlines
        STL 10:55
        4h 20m
        Nonstop
        SEA 13:15
        St. Louis - Seattle | Mon, Sep 28 |
        US$306 US$348
        12% off
        12% off
        US$348 US$306
      • SEA 15:41
        6h 46m
        1 stop
        STL 00:27
        Seattle - St. Louis | Thu, Sep 24 | American Airlines
        STL 05:43
        7h 28m
        1 stop
        SEA 11:11
        St. Louis - Seattle | Tue, Sep 29 | American Airlines
        US$159 US$348
        54% off
        54% off
        US$348 US$159
      • SEA 05:00
        7h 30m
        1 stop
        STL 14:30
        Seattle - St. Louis | Sat, Oct 17 | American Airlines
        STL 19:10
        7h
        1 stop
        SEA 00:10
        St. Louis - Seattle | Sat, Oct 24 | American Airlines
        US$159
        54% off
        US$348 US$159
      • SEA 15:41
        6h 46m
        1 stop
        STL 00:27
        Seattle - St. Louis | Mon, Sep 28 | American Airlines
        STL 05:00
        7h 9m
        1 stop
        SEA 10:09
        St. Louis - Seattle | Thu, Oct 1 | American Airlines
        US$159
        54% off
        US$348 US$159
      • SEA 05:30
        7h 14m
        1 stop
        STL 14:44
        Seattle - St. Louis | Tue, Sep 29 | American Airlines
        STL 05:00
        7h 9m
        1 stop
        SEA 10:09
        St. Louis - Seattle | Thu, Oct 1 | American Airlines
        US$159
        54% off
        US$348 US$159
      • SEA 16:27
        24h 50m
        1 stop
        STL 19:17
        Seattle - St. Louis | Tue, Sep 15 | Frontier Airlines
        STL 12:17
        23h 25m
        1 stop
        SEA 09:42
        St. Louis - Seattle | Tue, Sep 22 | Frontier Airlines
        US$160
        54% off
        US$348 US$160
      • SEA 06:00
        7h 14m
        1 stop
        STL 15:14
        Seattle - St. Louis | Sat, Sep 26 | Delta Air Lines
        STL 17:47
        8h 8m
        1 stop
        SEA 23:55
        St. Louis - Seattle | Fri, Oct 2 | Delta Air Lines
        US$161
        54% off
        US$348 US$161
      • SEA 23:59
        8h 32m
        1 stop
        STL 10:31
        Seattle - St. Louis | Mon, Sep 21 | Delta Air Lines
        STL 06:40
        10h 9m
        1 stop
        SEA 14:49
        St. Louis - Seattle | Thu, Sep 24 | Delta Air Lines
        US$162
        53% off
        US$348 US$162
      • SEA 23:50
        8h 48m
        1 stop
        STL 10:38
        Seattle - St. Louis | Fri, Oct 9 | Delta Air Lines
        STL 17:35
        8h 24m
        1 stop
        SEA 23:59
        St. Louis - Seattle | Tue, Oct 13 | Delta Air Lines
        US$162
        53% off
        US$348 US$162
      • SEA 15:41
        6h 46m
        1 stop
        STL 00:27
        Seattle - St. Louis | Sat, Sep 26 | American Airlines
        STL 07:21
        9h 30m
        1 stop
        SEA 14:51
        St. Louis - Seattle | Fri, Oct 2 | American Airlines
        US$166
        52% off
        US$348 US$166
      • SEA 13:00
        17h 25m
        1 stop
        STL 14:00
        Seattle - St. Louis | Sun, Sep 13 | Normal Airline
        STL 15:00
        6h
        Nonstop
        SEA 16:00
        St. Louis - Seattle | Tue, Sep 15 | Normal Airline
        More cheap flights
        More cheap flights
      • Cheapest nonstop
        SEA 18:00
        3h 59m
        Nonstop
        STL 23:59
        Seattle - St. Louis | Wed, Oct 14 | Alaska Airlines
        US$126 US$186
        32% off
        32% off
        US$186 US$126
      • SEA 12:35
        4h 3m
        Nonstop
        STL 18:38
        Seattle - St. Louis | Thu, Oct 1 | Alaska Airlines
        US$163 US$186
        12% off
        12% off
        US$186 US$163
      • SEA 06:00
        9h 19m
        1 stop
        STL 17:19
        Seattle - St. Louis | Fri, Oct 30 | Delta Air Lines
        US$81 US$186
        56% off
        56% off
        US$186 US$81
      • SEA 06:12
        8h 41m
        1 stop
        STL 16:53
        Seattle - St. Louis | Fri, Oct 30 | American Airlines
        US$83
        55% off
        US$186 US$83
      • SEA 06:00
        8h 47m
        1 stop
        STL 16:47
        Seattle - St. Louis | Mon, Oct 5 | Delta Air Lines
        US$83
        55% off
        US$186 US$83
      • SEA 23:57
        8h 21m
        1 stop
        STL 10:18
        Seattle - St. Louis | Mon, Oct 5 | American Airlines
        US$84
        55% off
        US$186 US$84
      • SEA 23:50
        8h 48m
        1 stop
        STL 10:38
        Seattle - St. Louis | Sun, Nov 8 | Delta Air Lines
        US$84
        55% off
        US$186 US$84
      • SEA 23:59
        8h 32m
        1 stop
        STL 10:31
        Seattle - St. Louis | Fri, Sep 25 | Delta Air Lines
        US$85
        54% off
        US$186 US$85
      • SEA 23:59
        8h 32m
        1 stop
        STL 10:31
        Seattle - St. Louis | Fri, Oct 2 | Delta Air Lines
        US$89
        52% off
        US$186 US$89
      • SEA 06:00
        7h 14m
        1 stop
        STL 15:14
        Seattle - St. Louis | Mon, Sep 21 | Delta Air Lines
        US$90
        52% off
        US$186 US$90
      • SEA 13:00
        17h 25m
        1 stop
        STL 14:00
        Seattle - St. Louis | Sun, Sep 13 | Normal Airline
        More cheap flights
        More cheap flights

Flight.News
Flights from Seattle to St. Louis operate an average of 10 times per day over the past 7 days, with a 38.1% on-time departure rate and a 95.0% on-time arrival rate.

Which airlines are the most popular for Seattle to St. Louis flights?

You can choose from 1 airlines that fly from Seattle to St. Louis, including Alaska Airlines, Delta Air Lines has lowest fares on this route.
Alaska Airlines logo Alaska Airlines
Airlines are determined based on actual purchased flight tickets from Seattle to St. Louis according to previous 12 months data from Trip.com.

Seattle to St. Louis Flight Information

The distance between Seattle and St. Louis is about 2,765.15 km. The average flying time from Seattle to St. Louis is around 3 hours 59 minutes. Based on Trip.com's latest data, travel demand is highest in July. The off-season for travel is November.

Cheapest one-way flight price US$81
Cheapest return ticket price US$159
Cheapest month November
Peak season for travel July
Flight distance 2,765.15 km
Average flight time 3 hours 59 minutes
Popular airline Alaska Airlines
Frequency ～15/week
Flight statistics for the Seattle–St. Louis route are based on aggregated booking data from Trip.com over the past 12 months.

Trip.com Price Trends on Flights from Seattle to St. Louis

Which month has the cheapest one-way flights from Seattle to St. Louis?

Average monthly one-way flight prices from Seattle to St. Louis, based on bookings made by Trip.com users over the past 12 months.

Based on Trip.com’s data, the cheapest month for flights from Seattle to St. Louis is October, with an average price of US$173; while the month with the highest flight price is usually December, with an average price of up to US$383.

US$383
US$278
US$173
US$68
    Cheapest
  • US$214
    Sep
  • US$173
    Oct
  • US$274
    Nov
  • US$383
    Dec
  • US$264
    Jan
  • US$227
    Feb
  • US$173
    Mar
  • US$179
    Apr
  • US$295
    May
  • US$244
    Jun
  • US$223
    Jul
  • US$287
    Aug

Frequently Asked Questions

  • What are the cheapest flights from Seattle to St. Louis (SEA-STL)?

    Based on Trip.com data, Delta Air Lines offers one-way fares as low as US$81 on Cheapest nonstop routes (e.g. SEA to STL on Fri, Oct 30), while American Airlines offers Cheapest nonstop round-trips from US$159 departing on Thu, Sep 24 and returning on Tue, Sep 29.
  • At the moment, you can catch a nonstop flight from Seattle to St. Louis with the following airlines, including: Alaska Airlines Selected airlines are based on historical data collected from flight bookings users made on Trip.com within the last 90 days.
  • It takes about 3 hours 59 minutes to fly from Seattle to St. Louis.
  • By analyzing data from all airlines on the Trip.com flight calendar, it looks like the best time to book a flight from Seattle to St. Louis is around 40 days (6 weeks) in advance, and the best time to fly is usually on Tuesday, Wednesday, and Saturday. Tuesday typically offers the cheapest flights for departure, while Saturday offers the best return deals.
  • Based on Trip.com data in the past 4 weeks, there is 34 flight per week flying from Seattle to St. Louis. You can check the weekly schedule for popular airlines on this route below: Alaska Airlines: S/M/T/W/T/F/S -- AS388 (08:28)
  • To find best deals on flights from Seattle to St. Louis, you can use various tools on Trip.com:
    · Be flexible with your travel dates to get the cheapest flight deal. Now the cheapest flight deal is on Fri, Oct 30, with one-way flights priced at just US$81.
    · Compare airlines strategically. Budget carriers often provide the lowest base fares, while we found the most affordable airline currently operating on this route is Alaska Airlines.
    · Set up price alerts to easily monitor ticket prices without having to check every day.
    · Check Trip.com flight deals and promo codes frequently.
    · Avoid peak season unless you book very early. It seems the peak season for St. Louis travel is around July.
    · Get exclusive promo codes for Trip.com app users.
  • The cheapest months to fly from Seattle to St. Louis is November, when demand for travel is lower.
  • You can land at any one of the following hubs in St. Louis: St. Louis Downtown Airport (CPS), and St. Louis Lambert International Airport (STL). Flying from Seattle-Tacoma International Airport to St. Louis Lambert International Airport (SEA-STL) is by far the most common option on this route.
  • The time difference between St. Louis and Seattle is 2h.
  • Tickets can only be changed or canceled if permitted by airline policy. To submit a change or cancellation request, go to the flight bookings page, select the option to change or cancel your booking, choose the relevant passengers and segment, and submit a request. Please note that additional charges may apply according to the airline ticket policy. However, if the flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For more details about change and cancellation policies, please check the customer support pages.
  • Based on Trip.com data for flights departing in the next 30 days, the average one-way fare from Seattle to St. Louis is US$203. Fares vary by travel date, airline and availability.
  • Based on Trip.com data for travel in the next 30 days, the average round-trip fare from Seattle to St. Louis is US$478. The final price depends on the outbound and return dates, airline and fare conditions.
  • Enter Seattle and St. Louis, choose your travel dates and passengers, then compare flights by price, duration and baggage. Select a fare, review the change and cancellation rules, enter traveler details and complete payment to receive your confirmation.
  • Frontier Airlinesare the most popular budget airlines flying from Seattle to St. Louis. Check baggage, seat and payment fees before comparing the final price.

Trip.com Airline Insights on Flights from Seattle to St. Louis

Which airline offers the cheapest direct flights from Seattle to St. Louis?

Data is based on the average price of all nonstop flights from Seattle to St. Louis on Trip.com over the past 12 months.

Based on Trip.com’s data from the past 12 months, Frontier Airlines provides the lowest-priced direct flights from Seattle to St. Louis, with fares starting at US$182.

US$147
US$182
US$217
US$252
US$287
Frontier Airlines
US$182
Frontier Airlines
Hawaiian Airlines
US$265
Hawaiian Airlines
American Airlines
US$268
American Airlines
Alaska Airlines
US$287
Alaska Airlines
Delta Air Lines
US$287
Delta Air Lines

Which airline operates the most flights from Seattle to St. Louis?

Total flights from Seattle to St. Louis across all airlines. (Based on Trip.com data from the past month)

Based on Trip.com’s data from the past month, Alaska Airlines/American Airlines operates the most frequent flights from Seattle to St. Louis, with 21 flights per week.

2
8
15
21
Alaska Airlines
21
Alaska Airlines
American Airlines
21
American Airlines
Cathay Pacific
13
Cathay Pacific
Japan Airlines
8
Japan Airlines
Qatar Airways
8
Qatar Airways

How many flights fly from Seattle to St. Louis daily?

The data is based on the flight numbers for each day of the week from Seattle to St. Louis within the Trip.com database over the past month.

Based on the past month's historical data from Trip.com, the number of flights from Seattle to St. Louis is the highest on Saturday and the lowest on Wednesday.

51
43
34
26
Highest
49
Mon
38
Tue
34
Wed
49
Thu
50
Fri
51
Sat
40
Sun

Explore More Popular Flights

Note: Prices shown on this page are the estimated lowest prices found in the last 24 hours and include all taxes and fees.

Book with no extra fees

Prices displayed on this page are all-inclusive (incl. taxes, fuel surcharges, Civil Aviation Development Fund, etc.), and all fees are clearly shown before you pay. Charges for checked baggage, onboard meals, Wi‑Fi, and other optional services are also included where applicable in the flight cards.

Real-time pricing updates

Prices, availability, and travel details on this page have been updated within the last 24 hours, and for many routes are refreshed in real time. The more popular the route, the more accurate and up-to-date the data.

Change & Cancellation Policy

Trip.com shows the change and cancellation rules for each ticket during the booking process, including all related fees and conditions. Please refer to the following scenarios:
Voluntary cancellation/change:
To request a change or cancellation, go to the flight bookings page, select the option to change or cancel your booking, choose the relevant passengers and flight segment, and submit your request. Please note that additional charges may apply based on the airline’s fare rules.
Cancellation/change due to a flight schedule change:
If your flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For full details of change and cancellation policies, please refer to the customer support pages.