$89 Cheap United flights Sacramento (SMF) to Seattle (SEA)

You'll discover cheap round-trip United Airlines flights from $168 from SMF to SEA by sorting your results from "Price (lowest to highest)" on Expedia. Or search for bargains from $89 for a one-way trip.**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 affordable United Airlines flights from Sacramento Intl. Airport (SMF) 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. Regardless of fare type and journey, the ideal day to book a domestic flight is usually Sunday and the most expensive is typically Monday. Passengers who book on a Sunday can save 6% on average compared to those who book 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 United Airlines's earliest flights from SMF to SEA by checking 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.

With a rewarding loyalty program, United Airlines is a top pick for many travelers heading from SMF to SEA. Plus, as a United Mileage Plus and One Key™ member booking through Expedia, you can earn OneKeyCash™* on eligible flights on top of your airline miles.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.