Flights to Tri-Cities from St. Louis - $139

View $139 flight on Tue, Sep 30, 2025Opens in a new window

Popular airlines from St. Louis to Tri-Cities

  • Alaska Airlines

    Alaska Airlines

  • Delta

    Delta

  • American Airlines

    American Airlines

  • United

    United

  • Hawaiian Airlines

    Hawaiian Airlines

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Cheap Flights from St. Louis to Tri-Cities (STL-PSC)

Prices were available within the past 7 days and start at $139 for one-way flights and $274 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
Sat, Nov 8 - Sat, Nov 15
STL
St. Louis
PSC
Pasco
$274 Roundtrip, found 5 hours ago
$274
Roundtrip
found 5 hours ago
Select Delta flight, departing Sat, Nov 8 from St. Louis to Pasco, returning Sat, Nov 15, priced at $274 found 5 hours ago
Delta
Wed, Aug 20 - Wed, Sep 3
STL
St. Louis
PSC
Pasco
$276 Roundtrip, found 13 hours ago
$276
Roundtrip
found 13 hours ago
Select Delta flight, departing Wed, Aug 20 from St. Louis to Pasco, returning Wed, Sep 3, priced at $276 found 13 hours ago
Alaska Airlines
Wed, Sep 17 - Wed, Sep 24
STL
St. Louis
PSC
Pasco
$279 Roundtrip, found 8 hours ago
$279
Roundtrip
found 8 hours ago
Select Alaska Airlines flight, departing Wed, Sep 17 from St. Louis to Pasco, returning Wed, Sep 24, priced at $279 found 8 hours ago
United
Wed, Sep 10 - Wed, Sep 24
STL
St. Louis
PSC
Pasco
$279 Roundtrip, found 3 days ago
$279
Roundtrip
found 3 days ago
Select United flight, departing Wed, Sep 10 from St. Louis to Pasco, returning Wed, Sep 24, priced at $279 found 3 days ago
Hawaiian Airlines
Mon, Aug 18 - Tue, Aug 26
STL
St. Louis
PSC
Pasco
$317 Roundtrip, found 13 hours ago
$317
Roundtrip
found 13 hours ago
Select Hawaiian Airlines flight, departing Mon, Aug 18 from St. Louis to Pasco, returning Tue, Aug 26, priced at $317 found 13 hours ago
American Airlines
Sat, Nov 8 - Sat, Nov 15
STL
St. Louis
PSC
Pasco
$364 Roundtrip, found 5 hours ago
$364
Roundtrip
found 5 hours ago
Select American Airlines flight, departing Sat, Nov 8 from St. Louis to Pasco, returning Sat, Nov 15, priced at $364 found 5 hours ago

Find the cheapest month to fly from St. Louis (STL) to Pasco (PSC)

October is typically the cheapest month to fly

From $267 - $820 per traveler.

Graph displaying average flight prices per month

Alternative airports

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Tri-Cities PSC. Cheapest option available. Flights from $389
PSC
Tri-Cities
Cheapest
Flights from $389
Select flight to Eastern Oregon Regional PDT. Flights from $507
PDT
Eastern Oregon Regional
Flights from $507
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