United Flight 640 Deals & Information (2025/2026)

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United Flight 640 Route Deals From $174

The cheapest prices found with in the last 7 days for return flights were $302 and $174 for one-way flights to Denver Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Tue, Jul 22 - Mon, Jul 28
YVR
Vancouver Intl.
DEN
Denver Intl.
$302 Roundtrip, found 5 days ago
$302
Roundtrip
found 5 days ago
Select United flight, departing Tue, Jul 22 from Vancouver Intl. to Denver Intl., returning Mon, Jul 28, priced at $302 found 5 days ago
Tue, Jul 22 - Mon, Jul 28
YVR
Vancouver Intl.
DEN
Denver Intl.
$322 Roundtrip, found 5 days ago
$322
Roundtrip
found 5 days ago
Select United flight, departing Tue, Jul 22 from Vancouver Intl. to Denver Intl., returning Mon, Jul 28, priced at $322 found 5 days ago
Thu, Sep 18 - Sun, Sep 21
YVR
Vancouver Intl.
DEN
Denver Intl.
$350 Roundtrip, found 18 hours ago
$350
Roundtrip
found 18 hours ago
Select United flight, departing Thu, Sep 18 from Vancouver Intl. to Denver Intl., returning Sun, Sep 21, priced at $350 found 18 hours ago
Tue, Jul 22 - Mon, Jul 28
YVR
Vancouver Intl.
DEN
Denver Intl.
$352 Roundtrip, found 5 days ago
$352
Roundtrip
found 5 days ago
Select United flight, departing Tue, Jul 22 from Vancouver Intl. to Denver Intl., returning Mon, Jul 28, priced at $352 found 5 days ago

Frequently asked questions

What route does flight number UA640 take?
UA640 is used on multiple routes, but the most common is between McCarran Intl. Airport (LAS) and O'Hare Intl. Airport (ORD). If you're lucky enough to score a direct flight, you'll land in around 3 hours and 48 minutes. Multi-stop flights can also use the same number, as can services on other routes.
How often is UA640 on time?
The most popular route of United Airlines flight number UA640 flies between Las Vegas, NV Airport (LAS-McCarran Intl.) and O'Hare Intl. Airport (ORD) and runs on time 70% of the time. Still, it's good to allow a little buffer room if this is your flight number. In the event of a delay, there is an average wait time of 27 minutes. This trip has a 1.45-star rating.
What terminal does UA640 fly out of?
If you're leaving from LAS, you'll most likely board from Terminal 3. The most popular route for UA640 is McCarran Intl. Airport (LAS) to ORD, which is a direct flight.
What kind of plane is on flight number UA640?
It's possible you'll be heading off on a Boeing 737-900 if you've booked a ticket from McCarran Airport to O'Hare Intl. Airport (ORD), a common route for flight UA640.
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 UA640 flight with Travelocity, please visit our Customer Service Portal.