$103 Cheap Frontier Airlines flights Seattle (SEA) to Chicago (ORD)

Landing cheap one-way Frontier Airlines flights from SEA to ORD from $103 on Expedia is simple — just filter by “Price (lowest to highest).” Alternatively, check out our budget-friendly round-trip fares from $227 for your next getaway.**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.

January is one of the cheapest months to jet away to Chicago with Frontier Airlines. You could also find fantastic deals on one-way and return tickets in February.

For cheap Frontier Airlines fares from Seattle - Tacoma Intl. Airport (SEA) to O’Hare Intl. Airport (ORD), start searching one to three months before your planned departure. Reserving domestic flights 34 to 86 days in advance could save you 25% compared to booking just 6 to 12 days ahead. The day you book can also affect the price you pay. Sunday tends to be the cheapest, while Monday is often the most expensive for domestic flights. You can save 6% on average by booking your trip on a Sunday.**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.

Enter your dates, press search and select the “Nonstop” filter on Expedia to find any direct flights from SEA to ORD with Frontier Airlines or another airline.

To find the earliest departures from SEA to ORD with Frontier Airlines, sort your results by “Morning” and “Early Morning.” Choosing an early flight usually means cancellations are less likely.**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.

Frontier Airlines flights from Seattle - Tacoma Intl. Airport (SEA) to Chicago come in to land at O’Hare Intl. Airport (ORD). This is the main gateway here.

With a rewarding loyalty program, Frontier Airlines is a top choice for many travelers journeying from SEA to ORD. Plus, if you’re a Frontier Miles and One Key™ member booking through Expedia, you can earn OneKeyCash™* on eligible flights along with your airline miles.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.

Depending on the ticket type you purchased, a fee is typically charged if you modify or cancel your flight more than 24 hours after confirmation. To find flexible plane tickets, select our “Changes included” and “No cancel fee” boxes while searching for flights. For more details on modifying or canceling your reservation, go to “Trips,” select your flight and tick “Manage Booking.”