United Flight 3631 Deals & Information (2025/2026)

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United Flight 3631 Route Deals From $45

The cheapest prices found with in the last 7 days for return flights were $148 and $45 for one-way flights to Washington Dulles Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Fri, Aug 8 - Tue, Aug 12
SBN
South Bend Intl.
IAD
Washington Dulles Intl.
$148 Roundtrip, found 16 hours ago
$148
Roundtrip
found 16 hours ago
Select United flight, departing Fri, Aug 8 from South Bend Intl. to Washington Dulles Intl., returning Tue, Aug 12, priced at $148 found 16 hours ago
Fri, Aug 8 - Tue, Aug 12
SBN
South Bend Intl.
IAD
Washington Dulles Intl.
$158 Roundtrip, found 16 hours ago
$158
Roundtrip
found 16 hours ago
Select United flight, departing Fri, Aug 8 from South Bend Intl. to Washington Dulles Intl., returning Tue, Aug 12, priced at $158 found 16 hours ago
Fri, Aug 8 - Tue, Aug 12
SBN
South Bend Intl.
IAD
Washington Dulles Intl.
$166 Roundtrip, found 16 hours ago
$166
Roundtrip
found 16 hours ago
Select United flight, departing Fri, Aug 8 from South Bend Intl. to Washington Dulles Intl., returning Tue, Aug 12, priced at $166 found 16 hours ago

Frequently asked questions

What route does flight number UA3631 take?
UA3631 serves multiple routes, but the most common is between Buffalo Niagara Intl. Airport (BUF) and ORD. If your flight goes direct, you'll arrive in 1 hour and 54 minutes. Multi-stop flights can also operate under this number, as can flights on other routes.
What kind of plane is on flight number UA3631?
If you're booked on flight UA3631 from Buffalo Niagara Intl. Airport (BUF) to O'Hare Intl. Airport (ORD), you'll most likely be on board an Embraer 170. Flight UA3631 serves multiple routes, but this is the busiest.
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 UA3631 flight with Travelocity, please visit our Customer Service Portal.