Alaska Airlines Flight WN321 Deals & Information (2025/2026)

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Alaska Airlines Flight 321 Route Deals From

The cheapest prices found with in the last 7 days for return flights were $123 and for one-way flights to Denver Intl. for the period specified. Prices and availability are subject to change. Additional terms apply.

Tue, Nov 4 - Tue, Nov 11
SEA
Seattle - Tacoma Intl.
DEN
Denver Intl.
$123 Roundtrip, found 5 days ago
$123
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Tue, Nov 4 from Seattle - Tacoma Intl. to Denver Intl., returning Tue, Nov 11, priced at $123 found 5 days ago
Wed, Sep 17 - Tue, Sep 30
SEA
Seattle - Tacoma Intl.
DEN
Denver Intl.
$128 Roundtrip, found 3 days ago
$128
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Wed, Sep 17 from Seattle - Tacoma Intl. to Denver Intl., returning Tue, Sep 30, priced at $128 found 3 days ago
Tue, Sep 30 - Tue, Oct 7
SEA
Seattle - Tacoma Intl.
DEN
Denver Intl.
$133 Roundtrip, found 3 days ago
$133
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Tue, Sep 30 from Seattle - Tacoma Intl. to Denver Intl., returning Tue, Oct 7, priced at $133 found 3 days ago
Wed, Sep 3 - Thu, Sep 11
SEA
Seattle - Tacoma Intl.
DEN
Denver Intl.
$147 Roundtrip, found 6 days ago
$147
Roundtrip
found 6 days ago
Select Alaska Airlines flight, departing Wed, Sep 3 from Seattle - Tacoma Intl. to Denver Intl., returning Thu, Sep 11, priced at $147 found 6 days ago
Wed, Sep 3 - Thu, Sep 4
SEA
Seattle - Tacoma Intl.
DEN
Denver Intl.
$153 Roundtrip, found 4 days ago
$153
Roundtrip
found 4 days ago
Select Alaska Airlines flight, departing Wed, Sep 3 from Seattle - Tacoma Intl. to Denver Intl., returning Thu, Sep 4, priced at $153 found 4 days ago
Thu, Sep 25 - Tue, Sep 30
SEA
Seattle - Tacoma Intl.
DEN
Denver Intl.
$154 Roundtrip, found 3 days ago
$154
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Thu, Sep 25 from Seattle - Tacoma Intl. to Denver Intl., returning Tue, Sep 30, priced at $154 found 3 days ago
Wed, Sep 3 - Wed, Sep 10
SEA
Seattle - Tacoma Intl.
DEN
Denver Intl.
$157 Roundtrip, found 1 hour ago
$157
Roundtrip
found 1 hour ago
Select Alaska Airlines flight, departing Wed, Sep 3 from Seattle - Tacoma Intl. to Denver Intl., returning Wed, Sep 10, priced at $157 found 1 hour ago
Wed, Sep 17 - Tue, Sep 30
SEA
Seattle - Tacoma Intl.
DEN
Denver Intl.
$159 Roundtrip, found 3 days ago
$159
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Wed, Sep 17 from Seattle - Tacoma Intl. to Denver Intl., returning Tue, Sep 30, priced at $159 found 3 days ago
Thu, Oct 2 - Thu, Oct 9
SEA
Seattle - Tacoma Intl.
DEN
Denver Intl.
$161 Roundtrip, found 5 days ago
$161
Roundtrip
found 5 days ago
Select Alaska Airlines flight, departing Thu, Oct 2 from Seattle - Tacoma Intl. to Denver Intl., returning Thu, Oct 9, priced at $161 found 5 days ago
Tue, Aug 12 - Tue, Aug 19
SEA
Seattle - Tacoma Intl.
DEN
Denver Intl.
$167 Roundtrip, found 3 days ago
$167
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Tue, Aug 12 from Seattle - Tacoma Intl. to Denver Intl., returning Tue, Aug 19, priced at $167 found 3 days ago
Mon, Oct 6 - Wed, Oct 8
SEA
Seattle - Tacoma Intl.
DEN
Denver Intl.
$177 Roundtrip, just found
$177
Roundtrip
just found
Select Alaska Airlines flight, departing Mon, Oct 6 from Seattle - Tacoma Intl. to Denver Intl., returning Wed, Oct 8, priced at $177 just found
Tue, Oct 7 - Wed, Oct 8
PAE
Seattle Paine Field Intl. Airport
DEN
Denver Intl.
$310 Roundtrip, found 3 days ago
$310
Roundtrip
found 3 days ago
Select Alaska Airlines flight, departing Tue, Oct 7 from Seattle Paine Field Intl. Airport to Denver Intl., returning Wed, Oct 8, priced at $310 found 3 days ago