Title: Flights to Pasco from St. Louis from $139 (STL to PSC) - Expedia.com ![blue bridge over Columbia river in Tri-cities Washington state](https://images.trvl-media.com/place/2878/9049bec3-53f1-48e4-9f2a-258938982d2f.jpg?impolicy=fcrop&w=1200&h=500&q=medium) ![](https://images.trvl-media.com/place/2878/9049bec3-53f1-48e4-9f2a-258938982d2f.jpg?impolicy=fcrop&w=1200&h=500&q=medium) # $139 Cheap Flights from St. Louis (STL) to Pasco (PSC) [View $139 flight on Wed, Apr 29, 2026](https://expedia.com/Flights-Search?trip=oneway&leg1=from:STL,to:PSC,departure:4/29/2026TANYT&passengers=children:0,adults:1,seniors:0,infantinlap:N&mode=search&options=sortby:price&paandi=true&flp=mdl:flights-flex-module,price:138.20&airProductToken=AQpuCjUIxJgBEgQzODQwGPJcIMx8KOnViwMw1NaLAzhFQABYAWoJTUFJTkJBU0lDcghWQVZTSDNCQwo1CMSYARIEMzY3NhjMfCDPFCiY14sDMOvYiwM4RUABWAFqCU1BSU5CQVNJQ3IIVkFWU0gzQkMSCggBEAEYASoCREwYASIECAEQASgCKAMoBDAB) ## Popular airlines from St. Louis Lambert Intl. Airport (STL) to Tri-Cities Airport (PSC) - ![](https://forever.travel-assets.com/flex/flexmanager/images/2024/09/23/landing_airline_sq_logo_AS.svg) Alaska Airlines [](https://www.expedia.com/Flights-Search?leg1=from:STL,to:PSC,departure:4/3/2026TANYT&leg2=from:PSC,to:STL,departure:4/10/2026TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&filters=[{"preferredAirlineFilterValue":{"carrierCode":"AS"}}]) - ![](https://forever.travel-assets.com/flex/flexmanager/images/2024/09/23/landing_airline_sq_logo_AA.svg) American Airlines [](https://www.expedia.com/Flights-Search?leg1=from:STL,to:PSC,departure:4/3/2026TANYT&leg2=from:PSC,to:STL,departure:4/10/2026TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&filters=[{"preferredAirlineFilterValue":{"carrierCode":"AA"}}]) - ![](https://forever.travel-assets.com/flex/flexmanager/images/2024/09/23/landing_airline_sq_logo_DL.svg) Delta [](https://www.expedia.com/Flights-Search?leg1=from:STL,to:PSC,departure:4/3/2026TANYT&leg2=from:PSC,to:STL,departure:4/10/2026TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&filters=[{"preferredAirlineFilterValue":{"carrierCode":"DL"}}]) - ![](https://forever.travel-assets.com/flex/flexmanager/images/2024/09/23/landing_airline_sq_logo_UA.svg) United [](https://www.expedia.com/Flights-Search?leg1=from:STL,to:PSC,departure:4/3/2026TANYT&leg2=from:PSC,to:STL,departure:4/10/2026TANYT&trip=roundtrip&passengers=adults:1,children:0,infantinlap:N&mode=search&pageId=0&filters=[{"preferredAirlineFilterValue":{"carrierCode":"UA"}}]) - ![](https://a.travel-assets.com/travel-assets-manager/pictogram-bex/light__notification.svg) ### Be in the know Get alerts if flight prices drop or rise\* - ![](https://a.travel-assets.com/travel-assets-manager/pictogram-bex/light__deals.svg) ### Book smarter Save up to 30% on select hotels after you book a flight\* - ![](https://a.travel-assets.com/travel-assets-manager/pictogram-bex/light__trophy.svg) ### Earn twice Earn your airline miles on top of our OneKeyCash [Learn about One Key](https://www.expedia.com/welcome-one-key) ## Cheap Flights from St. Louis to Pasco (STL-PSC) Prices were available within the past 7 days and start at $139 for one-way flights and $277 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply. All deals One way Roundtrip ![Delta](//images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/DL.gif) Tue, May 5 - Wed, May 20 STL St. Louis PSC Pasco $277 Roundtrip found 3 days ago [](https://expedia.com/Flights-Search?trip=roundtrip&leg1=from:STL,to:PSC,departure:5/5/2026TANYT&leg2=from:PSC,to:STL,departure:5/20/2026TANYT&passengers=children:0,adults:1,seniors:0,infantinlap:N&mode=search&options=sortby:price&paandi=true&flp=mdl:flights-flex-module,price:276.40&airProductToken=AQpuCjUIxJgBEgQxNDkyGPJcIPISKPGajAMwtpyMAzhFQABYAWoJTUFJTkJBU0lDcghWQVZTSDNCQwo1CMSYARIEMTcxMhjyEiDPFCiwnYwDMJSejAM4RUABWAFqCU1BSU5CQVNJQ3IIVkFWU0gzQkMSDAgBEAEYASoCREwyABgBIgQIARABKAIoAygEMAE) ![Delta](//images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/DL.gif) Tue, May 5 - Wed, May 20 STL St. Louis PSC Pasco $297 Roundtrip found 3 days ago [](https://expedia.com/Flights-Search?trip=roundtrip&leg1=from:STL,to:PSC,departure:5/5/2026TANYT&leg2=from:PSC,to:STL,departure:5/20/2026TANYT&passengers=children:0,adults:1,seniors:0,infantinlap:N&mode=search&options=sortby:price&paandi=true&flp=mdl:flights-flex-module,price:296.40&airProductToken=AQpuCjUIxJgBEgQxNDkyGPJcIPISKPGajAMwtpyMAzhFQABYAWoJTUFJTkJBU0lDcghWQVZTSDNCQwo1CMSYARIEMTcxMhjyEiDPFCiwnYwDMJSejAM4RUABWAFqCU1BSU5CQVNJQ3IIVkFWU0gzQkMSDAgBEAEYASoCREwyABgBIgQIARABKAIoAygEMAE) ![Delta](//images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/DL.gif) Wed, Apr 29 - Fri, May 8 STL St. Louis PSC Pasco $312 Roundtrip found 3 days ago [](https://expedia.com/Flights-Search?trip=roundtrip&leg1=from:STL,to:PSC,departure:4/29/2026TANYT&leg2=from:PSC,to:STL,departure:5/8/2026TANYT&passengers=children:0,adults:1,seniors:0,infantinlap:N&mode=search&options=sortby:price&paandi=true&flp=mdl:flights-flex-module,price:311.70&airProductToken=AQpuCjUIxJgBEgQzODQwGPJcIMx8KOnViwMw1NaLAzhFQABYAWoJTUFJTkJBU0lDcghWQVZTSDNCQwo1CMSYARIEMzY3NhjMfCDPFCiY14sDMOvYiwM4RUABWAFqCU1BSU5CQVNJQ3IIVkFWU0gzQkMKpAEKNQjEmAESBDM5NTUYzxQgkgEohryMAzDPvIwDOEVAAFgBaglNQUlOQkFTSUNyCFZGV1NBMEJECjQIxJgBEgM5NTMYkgEgzHwog8CMAzDSwYwDOEVAAVgBaglNQUlOQkFTSUNyCFZBVk5BMEJDCjUIxJgBEgQxMDUzGMx8IPJcKKPDjAMwhMSMAzhFQAFYAWoJTUFJTkJBU0lDcghWQVZOQTBCQxIKCAEQARgBKgJETBgBIgQIARABKAIoAygEMAE) ![American Airlines](//images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/AA.gif) Tue, May 12 - Tue, May 19 STL St. Louis PSC Pasco $317 Roundtrip found 1 hour ago [](https://expedia.com/Flights-Search?trip=roundtrip&leg1=from:STL,to:PSC,departure:5/12/2026TANYT&leg2=from:PSC,to:STL,departure:5/19/2026TANYT&passengers=children:0,adults:1,seniors:0,infantinlap:N&mode=search&options=sortby:price&paandi=true&flp=mdl:flights-flex-module,price:316.40&airProductToken=AQpnCjEIwYIBEgM4OTAY8lwg77kBKNnnjAMwpOmMAzhCQABYAWoFQkFTSUNyCE9WQUtVU0JWCjIIwYIBEgQ1MDA2GO-5ASDPFCjc6YwDMIjrjAM4QkABWAFqBUJBU0lDcghPVkFLVVNCVgpoCjIIwYIBEgQ2MzUzGM8UIO-5ASiYt40DMMC4jQM4QkAAWAFqBUJBU0lDcghPVkFLVVNCVgoyCMGCARIENDk2OBjvuQEg8lwos7mNAzDuuo0DOEJAAVgBagVCQVNJQ3IIT1ZBS1VTQlYSCggBEAEYASoCQUEYASIECAEQASgCKAMoBDAL) ![Alaska Airlines](//images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/AS.gif) Sat, May 2 - Sat, May 9 STL St. Louis PSC Pasco $317 Roundtrip found 15 hours ago [](https://expedia.com/Flights-Search?trip=roundtrip&leg1=from:STL,to:PSC,departure:5/2/2026TANYT&leg2=from:PSC,to:STL,departure:5/9/2026TANYT&passengers=children:0,adults:1,seniors:0,infantinlap:N&mode=search&options=sortby:price&paandi=true&flp=mdl:flights-flex-module,price:316.40&airProductToken=AQplCjAIwaYBEgM0NzMY8lwgkgEo0POLAzDg9YsDOFhAAFgBagVTQVZFUnIIUUgyT1hKQk4KMQjBpgESBDIwMjcYkgEgzxQo3_aLAzCg94sDOFhAAVgBagVTQVZFUnIIUUgyT1hKQk4KZQoxCMGmARIEMjEwMRjPFCCSASjswowDMKrDjAM4WEAAWAFqBVNBVkVScghRSDJPWEpCTgowCMGmARIDMzE0GJIBIPJcKMfEjAMwwsaMAzhYQAFYAWoFU0FWRVJyCFFIMk9YSkJOEgoIARABGAEqAkFTGAEiBAgBEAEoAigDKAQwDQ) ![Delta](//images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/DL.gif) Tue, May 5 - Wed, May 20 STL St. Louis PSC Pasco $322 Roundtrip found 3 days ago [](https://expedia.com/Flights-Search?trip=roundtrip&leg1=from:STL,to:PSC,departure:5/5/2026TANYT&leg2=from:PSC,to:STL,departure:5/20/2026TANYT&passengers=children:0,adults:1,seniors:0,infantinlap:N&mode=search&options=sortby:price&paandi=true&flp=mdl:flights-flex-module,price:321.40&airProductToken=AQpuCjUIxJgBEgQxNDkyGPJcIPISKPGajAMwtpyMAzhWQABYAWoJTUFJTkNMQVNDcghWQVZTSDNNRQo1CMSYARIEMTcxMhjyEiDPFCiwnYwDMJSejAM4VkABWAFqCU1BSU5DTEFTQ3IIVkFWU0gzTUUSDAgBEAEYASoCREwyABgBIgQIARABKAIoAygEMAE) ![Delta](//images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/DL.gif) Wed, Apr 22 - Fri, May 15 STL St. Louis PSC Pasco $328 Roundtrip found 3 days ago [](https://expedia.com/Flights-Search?trip=roundtrip&leg1=from:STL,to:PSC,departure:4/22/2026TANYT&leg2=from:PSC,to:STL,departure:5/15/2026TANYT&passengers=children:0,adults:1,seniors:0,infantinlap:N&mode=search&options=sortby:price&paandi=true&flp=mdl:flights-flex-module,price:327.01&airProductToken=AQqlAQo1CMSYARIEMTU3MRjyXCDgXCjDhIsDMKCFiwM4RUAAWAFqCU1BSU5CQVNJQ3IIVkFWU0gzQkMKNQjEmAESBDI4MjUY4FwgzHwo6YWLAzCKh4sDOEVAAVgBaglNQUlOQkFTSUNyCFZBVlNIM0JDCjUIxJgBEgQzNjc2GMx8IM8UKLiIiwMwi4qLAzhFQAFYAWoJTUFJTkJBU0lDcghWQVZTSDNCQwqmAQo1CMSYARIEMzk1NRjPFCCSASjmio0DMK-LjQM4RUAAWAFqCU1BSU5CQVNJQ3IIVkZXU0EwQkQKNQjEmAESAzgxMBiSASDjtAEorY6NAzC2kI0DOEVAAVgBaglNQUlOQkFTSUNyCFZBVk5BMEJDCjYIxJgBEgQyODY4GOO0ASDyXCi9kY0DMKWSjQM4RUABWAFqCU1BSU5CQVNJQ3IIVkFWTkEwQkMSCggBEAEYASoCREwYASIECAEQASgCKAMoBDAB) ![Delta](//images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/DL.gif) Sat, May 2 - Mon, May 18 STL St. Louis PSC Pasco $332 Roundtrip found 4 days ago [](https://expedia.com/Flights-Search?trip=roundtrip&leg1=from:STL,to:PSC,departure:5/2/2026TANYT&leg2=from:PSC,to:STL,departure:5/18/2026TANYT&passengers=children:0,adults:1,seniors:0,infantinlap:N&mode=search&options=sortby:price&paandi=true&flp=mdl:flights-flex-module,price:331.71&airProductToken=AQpuCjUIxJgBEgQxNDkyGPJcIPISKKj4iwMw7vmLAzhFQABYAWoJTUFJTkJBU0lDcghWQVZTSDNCQwo1CMSYARIEMTcxMhjyEiDPFCiP-4sDMPP7iwM4RUABWAFqCU1BSU5CQVNJQ3IIVkFWU0gzQkMKpgEKNQjEmAESBDM5NTUYzxQgkgEoxqyNAzCPrY0DOEVAAFgBaglNQUlOQkFTSUNyCFZGV1NBMEJECjUIxJgBEgM4MTAYkgEg47QBKI2wjQMwlrKNAzhFQAFYAWoJTUFJTkJBU0lDcghWQVZOQTBCQwo2CMSYARIEMjg2OBjjtAEg8lwonbONAzCFtI0DOEVAAVgBaglNQUlOQkFTSUNyCFZBVk5BMEJDEgwIARABGAEqAkRMMgAYASIECAEQASgCKAMoBDAB) ![Alaska Airlines](//images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/AS.gif) Wed, Apr 22 - Mon, Apr 27 STL St. Louis PSC Pasco $341 Roundtrip found 3 days ago [](https://expedia.com/Flights-Search?trip=roundtrip&leg1=from:STL,to:PSC,departure:4/22/2026TANYT&leg2=from:PSC,to:STL,departure:4/27/2026TANYT&passengers=children:0,adults:1,seniors:0,infantinlap:N&mode=search&options=sortby:price&paandi=true&flp=mdl:flights-flex-module,price:340.39&airProductToken=AQplCjAIwaYBEgMzMTQY8lwgkgEo2oeLAzDniYsDOFhAAFgBagVTQVZFUnIIUUgyT1hKQk4KMQjBpgESBDIzMDIYkgEgzxQovoqLAzD6iosDOFhAAVgBagVTQVZFUnIIUUgyT1hKQk4KZQoxCMGmARIEMjM2NhjPFCCSASiWwosDMNbCiwM4WEAAWAFqBVNBVkVScghHSDVPQVZCTgowCMGmARIDNDcyGJIBIPJcKNnMiwMwy86LAzhYQAFYAWoFU0FWRVJyCE9IMk9YVUJOEgoIARABGAEqAkFTGAEiBAgBEAEoAigDKAQwDQ) ![United](//images.trvl-media.com/media/content/expus/graphics/static_content/fusion/v0.1b/images/airlines/UA.gif) Sat, May 9 - Sat, May 16 STL St. Louis PSC Pasco $385 Roundtrip found 1 hour ago [](https://expedia.com/Flights-Search?trip=roundtrip&leg1=from:STL,to:PSC,departure:5/9/2026TANYT&leg2=from:PSC,to:STL,departure:5/16/2026TANYT&passengers=children:0,adults:1,seniors:0,infantinlap:N&mode=search&options=sortby:price&paandi=true&flp=mdl:flights-flex-module,price:384.40&airProductToken=AQpmCjEI1YIBEgQxNzI5GPJcIINpKNvGjAMw9ceMAzhMQABYAWoFMl9lY29yCExBSzJBUURTCjEI1YIBEgQxOTEzGINpIM8UKNDIjAMw6cmMAzhMQABYAWoFMl9lY29yCExBSzJBUURTEgoIARABGAEqAlVBGAEiBAgBEAEoAigDKAQwCw) ## Find the cheapest month to fly from St. Louis (STL) to Pasco (PSC) ### September is typically the cheapest month to fly From $273 - $712 per traveler. ## Frequently asked questions ### How much does a flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities) cost? ### What is the cheapest month to fly from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities)? ### Which airlines fly direct from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities)? ### What is the cheapest airline that flies from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities)? ### How do I find cheap flights from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities)? ### What is the best time to fly from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities)? ### What is the earliest flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities)? ### What are the most popular departure times for flights from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities)? ### How long does it take to fly from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities)? ### Can you fly business or first class from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities)? > - American Airlines > - Delta Air Lines > - United Airlines ### How do I earn miles on a St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities) flight with Expedia? ### What airports do you fly into for Pasco from Lambert-St. Louis Intl. (STL)? ### Is it cheaper to buy a plane ticket from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities) at the last minute? ### Is it cheaper to book a St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities) flight and hotel package? ### Can I cancel or change the date of my flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Pasco, WA (PSC-Tri-Cities)? ## Travel information | Origin airport | Lambert-St. Louis Intl. | | ------------------- | ------------------------------------------------- | | Destination airport | Tri-Cities | | Airlines serving | Alaska Airlines, American Airlines, Delta, United | | Roundtrip price | $276 | | Distance | 1543 mi | ## Book with confidence # St. Louis to Pasco Flights The cheapest times to fly from St. Louis to Pasco On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from St. Louis to Pasco are during the month of May. You can find some of the cheapest flights from St. Louis to Pasco with Expedia's search tool and vast selection of airlines. The best time to book a flight from St. Louis to Pasco Sunday is one of the best days to book for cheap flights from St. Louis to Pasco: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance. How to find cheap round-trip tickets from St. Louis to Pasco Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from St. Louis to Pasco in 2026\. You can also book with separate airlines for your outbound and return journeys, from $139 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference\*. This is available for a small fee, and is free to One Key Gold and Platinum tier members. Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap St. Louis to Pasco flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps. You could also save big by booking one of Expedia's [vacation packages](https://www.expedia.com/package-deals). Bundling together your St. Louis to Pasco airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures. \*Terms apply. Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023\. The percentages you see are averages. \*Flight schedules are subject to change. ## Explore a world of travel with Expedia - Lodging - Flights - [Pasco Hotels ](https://www.expedia.com/Pasco-Hotels.d2878.Travel-Guide-Hotels) - [Flights to Pasco ](https://www.expedia.com/Cheap-Flights-To-Pasco.d2878.Travel-Guide-Flights) - [Phoenix to Pasco ](https://www.expedia.com/lp/flights/178298/2878/phoenix-to-pasco) - [Dallas to Pasco ](https://www.expedia.com/lp/flights/178253/2878/dallas-to-pasco) \*Available to One Key members.