United Flight 2121 Deals & Information (2025/2026)

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United Flight 2121 Route Deals From $80

The cheapest prices found with in the last 7 days for return flights were $144 and $80 for one-way flights to Denver Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Thu, Sep 4 - Mon, Sep 8
MIA
Miami Intl.
DEN
Denver Intl.
$144 Roundtrip, found 1 hour ago
$144
Roundtrip
found 1 hour ago
Select United flight, departing Thu, Sep 4 from Miami Intl. to Denver Intl., returning Mon, Sep 8, priced at $144 found 1 hour ago
Thu, Aug 14 - Sun, Aug 17
MIA
Miami Intl.
DEN
Denver Intl.
$146 Roundtrip, found 18 hours ago
$146
Roundtrip
found 18 hours ago
Select United flight, departing Thu, Aug 14 from Miami Intl. to Denver Intl., returning Sun, Aug 17, priced at $146 found 18 hours ago
Thu, Sep 4 - Mon, Sep 8
MIA
Miami Intl.
DEN
Denver Intl.
$159 Roundtrip, found 1 hour ago
$159
Roundtrip
found 1 hour ago
Select United flight, departing Thu, Sep 4 from Miami Intl. to Denver Intl., returning Mon, Sep 8, priced at $159 found 1 hour ago
Thu, Aug 28 - Mon, Sep 1
MIA
Miami Intl.
DEN
Denver Intl.
$161 Roundtrip, found 3 hours ago
$161
Roundtrip
found 3 hours ago
Select United flight, departing Thu, Aug 28 from Miami Intl. to Denver Intl., returning Mon, Sep 1, priced at $161 found 3 hours ago
Thu, Jul 17 - Thu, Jul 31
MIA
Miami Intl.
DEN
Denver Intl.
$167 Roundtrip, found 1 day ago
$167
Roundtrip
found 1 day ago
Select United flight, departing Thu, Jul 17 from Miami Intl. to Denver Intl., returning Thu, Jul 31, priced at $167 found 1 day ago
Thu, Sep 4 - Mon, Sep 8
MIA
Miami Intl.
DEN
Denver Intl.
$176 Roundtrip, found 1 hour ago
$176
Roundtrip
found 1 hour ago
Select United flight, departing Thu, Sep 4 from Miami Intl. to Denver Intl., returning Mon, Sep 8, priced at $176 found 1 hour ago
Wed, Sep 3 - Tue, Sep 9
MIA
Miami Intl.
DEN
Denver Intl.
$203 Roundtrip, found 3 hours ago
$203
Roundtrip
found 3 hours ago
Select United flight, departing Wed, Sep 3 from Miami Intl. to Denver Intl., returning Tue, Sep 9, priced at $203 found 3 hours ago