United Flight 1251 Deals & Information (2025/2026)

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United Flight 1251 Route Deals From $171

The cheapest prices found with in the last 7 days for return flights were $328 and $171 for one-way flights to Los Angeles Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Frequently asked questions

What route does flight number UA1251 take?
UA1251 flies directly from BOS to O'Hare Intl. Airport (ORD). During this trip, you can expect to be in the air for approximately 2 hours and 47 minutes. It pays to book ahead to lock in your preferred seat.
What terminal does UA1251 fly out of?
Flight number UA1251 runs between Logan Intl. Airport (BOS) and O'Hare Intl. Airport (ORD), and travelers on this flight commonly depart from Terminal B.
What kind of plane is on flight number UA1251?
You're likely to be on the Boeing 737-800 if you're booked on flight number UA1251. Generally, this flight leaves from Logan Intl. Airport (BOS) and comes in to land at Chicago, IL Airport (ORD-O'Hare Intl.).
If I am not able to travel due to COVID-19, can I change my flight to a later date?
For more info about changing your UA1251 flight with Travelocity, please visit our Customer Service Portal.