St. Louis to Seattle Flights from HKD 84 incl. tax

Based on HopeGoo data, Delta Air Lines offers one-way fares as low as US$86 on Cheapest nonstop routes (e.g. STL to SEA on Fri, Apr 3), while Delta Air Lines offers Cheapest nonstop round-trips from US$156 departing on Mon, Apr 20 and returning on Sat, Apr 25.

At the moment, you can catch a nonstop flight from St. Louis to Seattle with the following airlines, including: Hawaiian Airlines Selected airlines are based on historical data collected from flight bookings users made on HopeGoo within the last 90 days.

It takes about 4 hours 29 minutes to fly from St. Louis to Seattle.

By analyzing data from all airlines on the HopeGoo flight calendar, it looks like the best time to book a flight from St. Louis to Seattle 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 HopeGoo data in the past 4 weeks, there is 20 flight per week flying from St. Louis to Seattle. You can check the weekly schedule for popular airlines on this route below: Hawaiian Airlines: S/M/T/W/T/-/S -- HA7001 (07:08)

To find best deals on flights from St. Louis to Seattle, you can use various tools on HopeGoo: · Be flexible with your travel dates to get the cheapest flight deal. Now the cheapest flight deal is on Fri, Apr 3, with one-way flights priced at just US$86. · Compare airlines strategically. Budget carriers often provide the lowest base fares, while we found the most affordable airline currently operating on this route is Hawaiian Airlines. · Set up price alerts to easily monitor ticket prices without having to check every day. · Check HopeGoo flight deals and promo codes frequently. · Avoid peak season unless you book very early. It seems the peak season for Seattle travel is around January. · Get exclusive promo codes for HopeGoo app users.

The cheapest months to fly from St. Louis to Seattle is November, when demand for travel is lower.

After crunching the numbers on our February flight calendar, it's currently cheapest to fly from St. Louis to Seattle on February 28, 2026 with Hawaiian Airlines, with prices starting at US$100.

You can land at any one of the following hubs in Seattle, with St. Louis Lambert International Airport to Seattle-Tacoma International Airport (STL-SEA) is by far the most common option on this route: King County (Boeing Field) International Airport (BFI) Kenmore Air - Lake Union (LKE) Seattle-Tacoma International Airport (SEA).

The time difference between Seattle and St. Louis 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 HopeGoo, 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.