United Flight 423 Deals & Information (2025/2026)

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United Flight 423 Route Deals From $79

The cheapest prices found with in the last 7 days for return flights were $165 and $79 for one-way flights to Denver Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Wed, Feb 18 - Sun, Feb 22
IAH
George Bush Intercontinental
DEN
Denver Intl.
$165 Roundtrip, found 4 hours ago
$165
Roundtrip
found 4 hours ago
Select United flight, departing Wed, Feb 18 from George Bush Intercontinental to Denver Intl., returning Sun, Feb 22, priced at $165 found 4 hours ago
Wed, Feb 18 - Sun, Feb 22
IAH
George Bush Intercontinental
DEN
Denver Intl.
$185 Roundtrip, found 4 hours ago
$185
Roundtrip
found 4 hours ago
Select United flight, departing Wed, Feb 18 from George Bush Intercontinental to Denver Intl., returning Sun, Feb 22, priced at $185 found 4 hours ago
Wed, Feb 18 - Sun, Feb 22
IAH
George Bush Intercontinental
DEN
Denver Intl.
$197 Roundtrip, found 4 hours ago
$197
Roundtrip
found 4 hours ago
Select United flight, departing Wed, Feb 18 from George Bush Intercontinental to Denver Intl., returning Sun, Feb 22, priced at $197 found 4 hours ago
Thu, Dec 4 - Fri, Dec 5
IAH
George Bush Intercontinental
DEN
Denver Intl.
$201 Roundtrip, found 7 hours ago
$201
Roundtrip
found 7 hours ago
Select United flight, departing Thu, Dec 4 from George Bush Intercontinental to Denver Intl., returning Fri, Dec 5, priced at $201 found 7 hours ago
Wed, Feb 18 - Sun, Feb 22
IAH
George Bush Intercontinental
DEN
Denver Intl.
$202 Roundtrip, found 4 hours ago
$202
Roundtrip
found 4 hours ago
Select United flight, departing Wed, Feb 18 from George Bush Intercontinental to Denver Intl., returning Sun, Feb 22, priced at $202 found 4 hours ago
Wed, Feb 18 - Sun, Feb 22
IAH
George Bush Intercontinental
DEN
Denver Intl.
$217 Roundtrip, found 4 hours ago
$217
Roundtrip
found 4 hours ago
Select United flight, departing Wed, Feb 18 from George Bush Intercontinental to Denver Intl., returning Sun, Feb 22, priced at $217 found 4 hours ago
Thu, Dec 4 - Fri, Dec 5
IAH
George Bush Intercontinental
DEN
Denver Intl.
$221 Roundtrip, found 7 hours ago
$221
Roundtrip
found 7 hours ago
Select United flight, departing Thu, Dec 4 from George Bush Intercontinental to Denver Intl., returning Fri, Dec 5, priced at $221 found 7 hours ago
Wed, Feb 18 - Sun, Feb 22
IAH
George Bush Intercontinental
DEN
Denver Intl.
$222 Roundtrip, found 4 hours ago
$222
Roundtrip
found 4 hours ago
Select United flight, departing Wed, Feb 18 from George Bush Intercontinental to Denver Intl., returning Sun, Feb 22, priced at $222 found 4 hours ago
Thu, Dec 4 - Fri, Dec 5
IAH
George Bush Intercontinental
DEN
Denver Intl.
$224 Roundtrip, found 7 hours ago
$224
Roundtrip
found 7 hours ago
Select United flight, departing Thu, Dec 4 from George Bush Intercontinental to Denver Intl., returning Fri, Dec 5, priced at $224 found 7 hours ago
Thu, Dec 4 - Fri, Dec 5
IAH
George Bush Intercontinental
DEN
Denver Intl.
$235 Roundtrip, found 7 hours ago
$235
Roundtrip
found 7 hours ago
Select United flight, departing Thu, Dec 4 from George Bush Intercontinental to Denver Intl., returning Fri, Dec 5, priced at $235 found 7 hours ago
Thu, Dec 4 - Fri, Dec 5
IAH
George Bush Intercontinental
DEN
Denver Intl.
$241 Roundtrip, found 7 hours ago
$241
Roundtrip
found 7 hours ago
Select United flight, departing Thu, Dec 4 from George Bush Intercontinental to Denver Intl., returning Fri, Dec 5, priced at $241 found 7 hours ago
Thu, Dec 4 - Fri, Dec 5
IAH
George Bush Intercontinental
DEN
Denver Intl.
$245 Roundtrip, found 7 hours ago
$245
Roundtrip
found 7 hours ago
Select United flight, departing Thu, Dec 4 from George Bush Intercontinental to Denver Intl., returning Fri, Dec 5, priced at $245 found 7 hours ago

Frequently asked questions

What route does flight number UA423 take?
UA423 is used on multiple routes. Mostly, UA423 flies directly from Portland Intl. Jetport to Dulles Intl. Airport. If that's your flight path, you'll be in the air for approximately 1 hour and 40 minutes.
What kind of plane is on flight number UA423?
If you've booked a seat on flight UA423 from Portland Intl. Jetport Airport (PWM) to Dulles Intl. Airport, there's a good chance you'll be on board an Airbus A319. This flight number serves numerous routes, but this is the most common one.
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 UA423 flight with Travelocity, please visit our Customer Service Portal.