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ALN to DEC: distance & flight time
Alton/St Louis (St Louis Regional Airport) → Decatur (Decatur Airport)
91 mi
146 km · 79 nm
42m
estimated nonstop flight time
—
time difference · heading northeast
See live ALN→DEC fares Phone-only fares on this route — call free
Flight time details
91 miles nonstop takes roughly 42m gate to gate, flying northeast. Add 45–90 minutes per connection if there's no nonstop service. Both airports share the same local time, so schedules read exactly as flown.
The two airports
- ALN — St Louis Regional Airport · Alton/St Louis, United States
- DEC — Decatur Airport · Decatur, United States
Distances are great-circle ("as the crow flies") — the same basis airlines use for frequent-flyer miles.
Alternate airports can cut this fare
Flying from or into a nearby airport is the #1 trick our agents use to beat online prices. Call and we'll compare every combination on one call.
Near ALN
- STL · St Louis Lambert International Airport20 mi away
- BLV · Scott AFB/Midamerica Airport26 mi away
- SUS · Spirit of St Louis Airport36 mi away
- SPI · Abraham Lincoln Capital Airport69 mi away
Frequently asked questions
How far is ALN from DEC?
The flight distance from Alton/St Louis (ALN) to Decatur (DEC) is 91 miles (146 km, 79 nautical miles), measured along the great-circle route airlines actually fly.
How long is the flight from ALN to DEC?
A nonstop flight takes about 42m gate to gate. Actual time varies with winds, routing and season — eastbound transatlantic flights, for example, are usually faster than the return.
What is the cheapest way to fly from ALN to DEC?
Compare live fares online, then call CheapoTrav — our agents have unpublished consolidator fares on ALN–DEC that never appear on search engines, with no booking fees.