United Flight 540 Deals & Information (2026/2027)

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United Flight 540 Route Deals From $140

The cheapest prices found with in the last 7 days for return flights were $257 and $140 for one-way flights to O'Hare Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Sat, Nov 7 - Tue, Nov 10
SAN
San Diego Intl.
ORD
O'Hare Intl.
$257 Roundtrip, found 16 hours ago
$257
Roundtrip
found 16 hours ago
Select United flight, departing Sat, Nov 7 from San Diego Intl. to O'Hare Intl., returning Tue, Nov 10, priced at $257 found 16 hours ago
Wed, Nov 11 - Sat, Nov 14
SAN
San Diego Intl.
ORD
O'Hare Intl.
$266 Roundtrip, found 2 days ago
$266
Roundtrip
found 2 days ago
Select United flight, departing Wed, Nov 11 from San Diego Intl. to O'Hare Intl., returning Sat, Nov 14, priced at $266 found 2 days ago
Sat, Nov 7 - Tue, Nov 10
SAN
San Diego Intl.
ORD
O'Hare Intl.
$267 Roundtrip, found 16 hours ago
$267
Roundtrip
found 16 hours ago
Select United flight, departing Sat, Nov 7 from San Diego Intl. to O'Hare Intl., returning Tue, Nov 10, priced at $267 found 16 hours ago
Tue, Dec 8 - Tue, Dec 15
SAN
San Diego Intl.
ORD
O'Hare Intl.
$287 Roundtrip, found 3 days ago
$287
Roundtrip
found 3 days ago
Select United flight, departing Tue, Dec 8 from San Diego Intl. to O'Hare Intl., returning Tue, Dec 15, priced at $287 found 3 days ago
Sat, Nov 7 - Tue, Nov 10
SAN
San Diego Intl.
ORD
O'Hare Intl.
$290 Roundtrip, found 16 hours ago
$290
Roundtrip
found 16 hours ago
Select United flight, departing Sat, Nov 7 from San Diego Intl. to O'Hare Intl., returning Tue, Nov 10, priced at $290 found 16 hours ago
Sat, Nov 7 - Tue, Nov 10
SAN
San Diego Intl.
ORD
O'Hare Intl.
$291 Roundtrip, found 16 hours ago
$291
Roundtrip
found 16 hours ago
Select United flight, departing Sat, Nov 7 from San Diego Intl. to O'Hare Intl., returning Tue, Nov 10, priced at $291 found 16 hours ago

Frequently asked questions

What route does flight number UA540 take?
You'll be landing at SAN from Denver Intl. Airport (DEN) if you've booked a ticket on flight number UA540. You'll be airborne for 2 hours and 26 minutes on this trip. It's also good to note that the service conveniently operates non-stop.
How often is UA540 on time?
People jetsetting on United Airlines flight number UA540 should be mindful that 76% of these flights depart as scheduled. If your trip experiences a delay, the typical wait is approximately 18 minutes. This route has a star rating of 2.2.
What kind of plane is on flight number UA540?
Prepare to jump on board a Boeing 737-800 if you have a seat on flight UA540. Most services from DIA airport to San Diego Airport use this model of aircraft.
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 UA540 flight with Travelocity, please visit our Customer Service Portal.