United Flight UA4521 Deals & Information (2025/2026)

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United Flight 4521 Route Deals From $70

The cheapest prices found with in the last 7 days for return flights were $137 and $70 for one-way flights to Buffalo Niagara Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Thu, Nov 13 - Mon, Nov 17
EWR
Newark Liberty Intl. Airport
BUF
Buffalo Niagara Intl.
$137 Roundtrip, found 1 day ago
$137
Roundtrip
found 1 day ago
Select United flight, departing Thu, Nov 13 from Newark Liberty Intl. Airport to Buffalo Niagara Intl., returning Mon, Nov 17, priced at $137 found 1 day ago
Sun, Aug 10 - Thu, Aug 14
EWR
Newark Liberty Intl. Airport
BUF
Buffalo Niagara Intl.
$150 Roundtrip, found 1 day ago
$150
Roundtrip
found 1 day ago
Select United flight, departing Sun, Aug 10 from Newark Liberty Intl. Airport to Buffalo Niagara Intl., returning Thu, Aug 14, priced at $150 found 1 day ago
Thu, Nov 13 - Mon, Nov 17
EWR
Newark Liberty Intl. Airport
BUF
Buffalo Niagara Intl.
$155 Roundtrip, found 1 day ago
$155
Roundtrip
found 1 day ago
Select United flight, departing Thu, Nov 13 from Newark Liberty Intl. Airport to Buffalo Niagara Intl., returning Mon, Nov 17, priced at $155 found 1 day ago
Thu, Aug 14 - Mon, Aug 18
EWR
Newark Liberty Intl. Airport
BUF
Buffalo Niagara Intl.
$157 Roundtrip, found 6 days ago
$157
Roundtrip
found 6 days ago
Select United flight, departing Thu, Aug 14 from Newark Liberty Intl. Airport to Buffalo Niagara Intl., returning Mon, Aug 18, priced at $157 found 6 days ago
Tue, Jul 15 - Sun, Jul 20
EWR
Newark Liberty Intl. Airport
BUF
Buffalo Niagara Intl.
$160 Roundtrip, found 5 hours ago
$160
Roundtrip
found 5 hours ago
Select United flight, departing Tue, Jul 15 from Newark Liberty Intl. Airport to Buffalo Niagara Intl., returning Sun, Jul 20, priced at $160 found 5 hours ago
Tue, Jul 8 - Wed, Jul 9
EWR
Newark Liberty Intl. Airport
BUF
Buffalo Niagara Intl.
$171 Roundtrip, found 6 hours ago
$171
Roundtrip
found 6 hours ago
Select United flight, departing Tue, Jul 8 from Newark Liberty Intl. Airport to Buffalo Niagara Intl., returning Wed, Jul 9, priced at $171 found 6 hours ago
Mon, Jul 21 - Thu, Jul 31
EWR
Newark Liberty Intl. Airport
BUF
Buffalo Niagara Intl.
$181 Roundtrip, found 5 hours ago
$181
Roundtrip
found 5 hours ago
Select United flight, departing Mon, Jul 21 from Newark Liberty Intl. Airport to Buffalo Niagara Intl., returning Thu, Jul 31, priced at $181 found 5 hours ago
Sun, Jun 29 - Sat, Jul 5
EWR
Newark Liberty Intl. Airport
BUF
Buffalo Niagara Intl.
$183 Roundtrip, found 5 days ago
$183
Roundtrip
found 5 days ago
Select United flight, departing Sun, Jun 29 from Newark Liberty Intl. Airport to Buffalo Niagara Intl., returning Sat, Jul 5, priced at $183 found 5 days ago
Fri, Jul 4 - Tue, Jul 8
EWR
Newark Liberty Intl. Airport
BUF
Buffalo Niagara Intl.
$184 Roundtrip, found 1 day ago
$184
Roundtrip
found 1 day ago
Select United flight, departing Fri, Jul 4 from Newark Liberty Intl. Airport to Buffalo Niagara Intl., returning Tue, Jul 8, priced at $184 found 1 day ago
Mon, Jun 30 - Sat, Jul 5
EWR
Newark Liberty Intl. Airport
BUF
Buffalo Niagara Intl.
$188 Roundtrip, found 18 hours ago
$188
Roundtrip
found 18 hours ago
Select United flight, departing Mon, Jun 30 from Newark Liberty Intl. Airport to Buffalo Niagara Intl., returning Sat, Jul 5, priced at $188 found 18 hours ago

Frequently asked questions

What route does flight number UA4521 take?
You'll arrive into ORD from CLE if you're traveling on flight number UA4521. You'll be in the air for 1 hour and 28 minutes during this journey. It's also worthwhile noting that the service conveniently operates non-stop.
What kind of plane is on flight number UA4521?
You'll likely be boarding a Canadair (Bombardier) Regional Jet 550 if you're on flight number UA4521. Generally, this flight takes off from Hopkins Intl. Airport (CLE) and touches down 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 UA4521 flight with Travelocity, please visit our Customer Service Portal.