United AirlinesUA
Flights UA3301 09:30 Fr
live
Direct flights from St Louis (STL) to Louisville (SDF): 1 nonstop departure observed each week across 1 airline. The nonstop covers 408 km, an estimated 1 hour 1 minutes in the air. Measured by Pro Flight Search from live flight boards at St Louis and Louisville. Updated 13 September 2026 at 18:36 UTC.
STL
St Louis
smooth · +11
SDF
Louisville
smooth · +0
408 km · ~1h 01m est.
Running clean · 1 airline · 1x weekly · nonstop
92 / 100
route health from live STL and SDF delay boards
Flight time~1h 01mestimated from route distance
Weekly departures1x1 direct airline on the leg
The week
scheduled departures · origin local time06121824
Mon
Tue
Wed
Thu
Fri
Sat
Sun
United Airlines
Each mark is a scheduled departure at its origin-local time, observed operating in the last 7 days. Today is highlighted.
Who flies it
observed on the boards · 7 daysAirports right now
live boardsWeather lens
Current conditions put the pressure at STL and SDF: 43% odds of a 15+ minute delay and around +8 min expected when it bites, measured from this route's own weather-matched delay history. See live delays → · Weather risk by airport →
next sweep in 120s
How the St Louis to Louisville route actually runs
Pro Flight Search records official board updates for nonstop STL to SDF flights through the day: schedules, estimates, gate pushes and actual departures. The verdict above comes from operated flights, so it reflects what this route does rather than what the timetable promises.
Planning around a delay? Live airport delays · Weather delay risk map · Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
Cite this data
Journalists, bloggers, and researchers may cite this page with attribution and a link to Pro Flight Search.
Suggested citation
Pro Flight Search — St Louis (STL) to Louisville (SDF) route reliability, measured from operated flights on official airport boards.
Canonical URL
How we measure this →
https://proflightsearch.com/search-flights/STL-SDF
STL to SDF questions
Is STL–SDF running on time right now?
Smooth skies ahead. The departure side at STL is the weaker end, route health score 92/100. The airports section above carries the live status and delay window at both ends.
How long is the flight from STL to SDF?
Great-circle distance is 408 km. With typical jet cruise speed plus taxi, climb and descent, expect roughly 59–65 min gate-to-gate on this route.
How often does STL–SDF fly?
United Airlines runs the route with about 1 flight a week (fri). Since one carrier owns the route, a single disruption tends to ripple through the day.
What does the route health score measure?
A blend of departure-side delay at STL and arrival-side delay at SDF, computed from rolling delay windows (refreshed every 40 minutes) with a daily-rollup fallback. Current MVFR, IFR, or LIFR endpoint weather caps the score when flight rules can limit throughput. Higher is healthier: 100 means operations are clean at both ends.
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