United Flight 400 Deals & Information (2025/2026)

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United Flight 400 Route Deals From $109

The cheapest prices found with in the last 7 days for return flights were $237 and $109 for one-way flights to Harry Reid Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Tue, Jul 15 - Tue, Jul 22
EWR
Newark Liberty Intl. Airport
LAS
Harry Reid Intl.
$237 Roundtrip, found 1 hour ago
$237
Roundtrip
found 1 hour ago
Select United flight, departing Tue, Jul 15 from Newark Liberty Intl. Airport to Harry Reid Intl., returning Tue, Jul 22, priced at $237 found 1 hour ago

Frequently asked questions

What route does flight number UA400 take?
UA400 operates from Dulles Intl. Airport to Raleigh–Durham Airport and is a direct flight. This trip takes 1 hour and 11 minutes.
What kind of plane is on flight number UA400?
The route for flight number UA400 is generally Dulles Intl. Airport to RDU, and the Boeing 737-800 is the aircraft model you’ll probably 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 UA400 flight with Travelocity, please visit our Customer Service Portal.