$89 Cheap Delta flights Colorado Springs (COS) to Seattle (SEA)

Scoring cheap one-way Delta Air Lines flights from COS to SEA from $89 on Expedia is easy --- just filter by "Price (lowest to highest)." Or check out our budget-friendly return fares from $146 for your next exciting vacation.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

Search for cheap Delta Air Lines flights from Colorado Springs Airport (COS) to Seattle - Tacoma Intl. Airport (SEA) one to three months prior to your departure date. Travelers who book domestic flights 34 to 86 days in advance can save 25% compared to those who book just 6 to 12 days ahead. No matter the fare type and journey, the best day of the week to book a domestic flight is usually Sunday and the most expensive day tends to be Monday. Passengers who book on a Sunday can save 6% on average compared to those who book their travel on a Monday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.

Browse Delta Air Lines's earliest flights from COS to SEA by using our "Morning" and "Early Morning" filters. Not only will you arrive sooner, early departures also experience 20% fewer cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.

Offering an excellent in-flight experience and a rewarding loyalty program, Delta Air Lines is a top choice for many travelers flying from COS to SEA. Also, if you're a Delta SkyMiles and One Key™ member booking through Expedia, you could earn OneKeyCash™* on eligible flights on top of your airline miles, which can be spent on future trips.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.