St Louis to Seattle (STL–BFI) — Airlines, Schedules & Connections

STL Airport Page →
1,706 mi airlines charter/private 1/wk
On-time Some delays Frequent delays
Flight Schedule No service Verified 34m ago
Also flown by charter / private operators: NetJets Aviation.
Nonstop Charter / private 1-Stop 2-Stop Hide separate tickets Hide overnight Hide codeshares
  Flight Airline AC Dep Arr Dur OTP Sched  
✈ Nonstop

No flights match your filters.

No scheduled airline flights on this route — it's flown by charter / private operators (). No nonstop flights on this route. connecting options below.

✦ 1-STOP More options, longer trips
✧ 2-STOP Loading... Reach the hardest destinations
St Louis to Seattle
Connecting service available through multiple hubs.
1 Airlines 1,706 mi 3h 54m nonstop -2h behind

STL–BFI had nonstop service from Sun Country Airlines, last on the schedule in September 2026. There's no nonstop on it right now, so today you'd fly it with one stop. The connecting options below are sorted by layover. Nonstop, it's about 1,706 miles in 3h 54m.

Also explore Browse available seat maps STL Routes BFI Routes STL Live Flights BFI Live Flights STL Delays
All flights from Seattle (BFI) Seattle to St Louis flights
Carriers on this route

Airline Landscape

Carriers that operated nonstop STL–BFI service, compared side by side.
Airline Freq/wk Aircraft Duration Dep OTP Alliance Codeshares
SY Sun Country Airlines 0 – – 100% – –
Alliance coverage
Unaffiliated: SY (0 flights/wk, 0%)
OTP based on airport-level delay snapshots. Duration ranges reflect seasonal/directional variation.
Connections

Connection Landscape

1-stop and 2-stop options for STL to BFI.
1-STOP
One-Stop Connections
0
Hubs
–
Fastest
–
Longest
Verified with published schedule alignment and minimum connection time.
2-STOP
Two-Stop Connections
0
Candidates
Two-stop connections loaded in the connections tab above.
Connections computed from published schedules with minimum connection time verification. Use the interactive explorer above the fold to filter by airline, tier, and layover time.
Reliability

On-Time Performance

What to expect at each end of your journey.
Outbound
STL → BFI
100%
Generally reliable. Most flights run on time.
Departing
100%
Return
BFI → STL
25%
Frequent delays expected. Consider flexible booking.
Arriving
25%
OTP = percentage of flights arriving within 15 min of schedule. Based on airport-level delay snapshots. STL delays →
Know before you go

Travel Essentials

Practical planning for this route.
Time Difference
-2h
Seattle is 2 hours behind St Louis.
STL: CDT · BFI: PDT

When it's 6:00 PM in St Louis, it's 4:00 PM in Seattle.
Distance & Flight Time
1,706 mi / 2,745 km
Nonstop flight time is approximately 3h 54m gate to gate.
Facts

STL–BFI Quick Facts

Key statistics for the St Louis to Seattle route.
Route details
Distance1,706 mi / 2,745 km
Flight time3h 54m
Time difference-2 hours
Airlines (nonstop)1
1-stop connectionsAvailable
Origin: STL
Full nameSt. Louis Lambert International Airport
IATA / ICAOSTL / KSTL
TimezoneAmerica/Chicago
Passengers/yr15.6M
Elevation618 ft / 188 m
Destination: BFI
Full nameKing County International Airport - Boeing Field
IATA / ICAOBFI / KBFI
TimezoneAmerica/Los_Angeles
Passengers/yr0.1M
Elevation21 ft / 6 m
FAQ

Frequently Asked Questions

Common questions about STL to BFI flights.
Nonstop flights from St. Louis Lambert International Airport to King County International Airport - Boeing Field take about 3h 54m gate to gate. The route covers 1,706 miles.
1 airline operated the nonstop from STL to BFI: Sun Country Airlines. The last scheduled nonstop was in September 2026. There's no nonstop right now, so today you'd fly it with one stop. See the connection options above, ranked by layover.
Not right now. The last scheduled nonstop was in September 2026. You can still fly it with one stop, and the connecting options above are sorted by layover. Nonstop, the hop took about 3h 54m.
Yes, 1-stop connections are available, ranked by layover time.
On a single ticket, yes. Your bags are checked through to BFI and move between planes without you. On two separate tickets you collect your bags at the connecting airport and recheck them, so build in extra layover time.
Seattle is 2 hours behind St Louis.
Yes, return flights from BFI to STL are available. Use the direction toggle at the top to view the return schedule.
Click the 'Search Flights' button to check availability and prices on Google Flights. You can also compare airlines and schedules on this page to find the best option.
See the On-Time Performance section for the latest delay data at both airports. This shows departure and arrival reliability to help you plan.
Route data is updated regularly from official airline schedules. On-time performance data comes from recent airport delay snapshots.

Flights from STL to BFI

St. Louis Lambert International Airport (STL) and King County International Airport - Boeing Field (BFI) had nonstop service from Sun Country Airlines, last on the schedule in September 2026. The nonstop is dormant right now, so the way to fly it today is one connection, and the options above are sorted by layover.

STL to BFI Flight Duration and Schedule

Nonstop flight time from STL to BFI is about 3 hours 54 minutes gate to gate. The route covers a distance of 1,706 miles (2,745 km).

Connecting Options and Alternatives

1-stop connecting options are also available. Two-stop connections are also available via intermediate hubs.