United Flight 3639 Deals & Information (2025/2026)

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United Flight 3639 Route Deals From $162

The cheapest prices found with in the last 7 days for return flights were $234 and $162 for one-way flights to Newark Liberty Intl. Airport for the period specified. Prices and availability are subject to change. Additional terms apply.

Wed, Aug 6 - Sat, Aug 9
MCI
Kansas City Intl.
EWR
Newark Liberty Intl. Airport
$234 Roundtrip, found 16 hours ago
$234
Roundtrip
found 16 hours ago
Select United flight, departing Wed, Aug 6 from Kansas City Intl. to Newark Liberty Intl. Airport, returning Sat, Aug 9, priced at $234 found 16 hours ago
Wed, Aug 6 - Sat, Aug 9
MCI
Kansas City Intl.
EWR
Newark Liberty Intl. Airport
$244 Roundtrip, found 16 hours ago
$244
Roundtrip
found 16 hours ago
Select United flight, departing Wed, Aug 6 from Kansas City Intl. to Newark Liberty Intl. Airport, returning Sat, Aug 9, priced at $244 found 16 hours ago
Wed, Aug 20 - Sat, Aug 23
MCI
Kansas City Intl.
EWR
Newark Liberty Intl. Airport
$266 Roundtrip, found 15 hours ago
$266
Roundtrip
found 15 hours ago
Select United flight, departing Wed, Aug 20 from Kansas City Intl. to Newark Liberty Intl. Airport, returning Sat, Aug 23, priced at $266 found 15 hours ago

Frequently asked questions

What route does flight number UA3639 take?
Flight number UA3639 flies directly from ORD to BUF. During this trip, expect to be in the air for about 1 hour and 33 minutes. It pays to book ahead to secure your favorite seat.
What terminal does UA3639 fly out of?
Flight number UA3639 runs between ORD and Buffalo Niagara International Airport, and travelers with a seat on this flight usually board the aircraft from Terminal 2.
What kind of plane is on flight number UA3639?
The route for UA3639 is usually O'Hare Airport to Buffalo Niagara Intl. Airport (BUF), and the Embraer 170 is the type of aircraft you're likely to be flying with.
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 UA3639 flight with Travelocity, please visit our Customer Service Portal.