UA503 BostonBOS · 10:36 ChicagoORD · 12:29
UA503 by United Airlines flies from Boston (BOS) to Chicago (ORD) for the Mon, Oct 12 departure.
arrived at ORD · 25 min early
The route today
live boardsWeather lens
Delay & cancellation outlook for this flight
Measured, 90-day sampleConditions at BOS and ORD are near their clear-air norm right now, so this reflects the route's recent baseline rather than a weather penalty. For this route and airline, under conditions like today's, over the last 90 days.
Pro Flight Search tracking, 90 days · the weather × delay correlation study → · live weather risk by airport →
When it flies
scheduled departuresEach mark is a scheduled departure at its origin-local time. Today is highlighted.
Other Boston to Chicago flights today
same route · United AirlinesIf UA503 is cancelled, these are the other United Airlines nonstop flights from Boston to Chicago on the same day, with scheduled departure times in BOS local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How UA503 actually runs
Pro Flight Search has tracked every published board update for UA503 across the BOS and ORD boards: schedule changes, gate pushes and actual clocks. Early read — pattern not clear yet. Only 2 completed legs so far: landed +5 min. Not enough to call it.
The verdict above is that record speaking, so it reflects how UA503 operates rather than what the timetable promises. Numbers refresh as new flights operate.
How this operation is measured
Board log
scheduled → actual, per operationBoard clocks recorded as BOS and ORD published them.
Planning around UA503? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
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Pro Flight Search — UA503 Boston to Chicago on-time performance, measured from the BOS and ORD airport boards.
https://proflightsearch.com/flight/UA503
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