$69 Cheap Flights from Seattle (SEA) to Denver (DEN)

Seattle (SEA) to Denver (DEN) at a glance

Travel between Seattle (SEA) and Denver (DEN) with a range of airlines catering to this domestic short-haul route. You can choose from full-service or low-cost carriers to discover the best option that aligns with your budget and schedule. As you plan your journey, consider the flight time and explore Denver's iconic attractions and vibrant neighborhoods. Find essential details for flights from Seattle - Tacoma International Airport (SEA) to Denver International Airport (DEN).

• Fastest flight duration: around 2h 45m non-stop
• Route distance: roughly 1,000 miles (1,610 km)
• Flights per week: around 90+ flights with multiple daily departures on average
• Typical fares (one-way): economy tickets often range from $50–$270, depending on seasonality and how far ahead you book

Flights from Seattle - Tacoma International Airport (SEA) to Denver International Airport (DEN)

According to recent traveler bookings, here are the top airlines preferred for flights from Seattle to Denver, featuring both non-stop and one-stop options. Many travelers find convenience with popular layover airports like Salt Lake City International Airport (SLC) with a 55-minute layover, Portland International Airport (PDX) with about a 2-hour layover, and Harry Reid International Airport (LAS) with a 1 hour and 45-minute layover. This variety allows you to compare prices, total travel times, and cabin classes to craft your ideal itinerary.

• Alaska Airlines: A comprehensive service provider that delivers both non-stop and one-stop flights, with one-way ticket prices generally falling between $60 and $305. It represents around 29% of departures for this route, with an average non-stop flight duration of 2 hours and 45 minutes.
• United: This full-service airline offers non-stop and one-stop options, with one-way fares usually ranging from $70 to $325. United accounts for about 25% of the departures on this route, maintaining a standard non-stop travel time of 2 hours and 45 minutes.
• Delta: A full-service airline providing both non-stop and one-stop service, Delta's one-way fares typically range from $55 to $285. It holds approximately 21% of the departures for this route, with a common non-stop journey time of 2 hours and 45 minutes.
• Southwest Airlines: As a budget airline, Southwest offers non-stop and one-stop flights, with one-way prices usually between $50 and $275. It comprises around 15% of departures on this route, featuring a typical non-stop flight time of 2 hours and 45 minutes.
• Frontier Airlines: This low-cost carrier provides non-stop and one-stop options, with one-way fares typically ranging from $50 to $205. Frontier makes up roughly 9% of the departures on this route, with an average non-stop travel duration of 2 hours and 45 minutes.

Travelers flying from Seattle to Denver have the option to enhance their journey by upgrading their flight. Leading airlines include Delta, which provides first class and premium economy cabins; Alaska Airlines, offering first class and business class; and United, featuring first class and premium economy service.

Best time to fly from Seattle (SEA) to Denver (DEN)

The most popular months for travelers flying from Seattle to Denver are March, April, and August, when peak temperatures in Denver reach up to 71.2°F in August. If you prefer quieter travel, consider October, the least busy and relatively cheaper time to visit with fewer crowds and temperatures around 50.2°F. For better deals, January usually offers the lowest average one-way fare around $142. Flight availability peaks in June, with approximately 120 flights per week, making it easier to find convenient departure times. January has the fewest flights, with approximately 73 flights per week.

• Cheapest time to fly: January usually offers good deals with average one-way fare around $142, roughly 6% cheaper than the yearly average.
• More budget-friendly months to fly: October, May, and April typically offer average one-way fares of around $145.
• Most flight options: June has the highest number of flights from Seattle to Denver, with approximately 120 flights per week, giving you more flexibility in scheduling your trip.

*Average one-way fare is based on Expedia flight booking data from January 2025 to April 2026 for the specified route and travel class and may change depending on availability, dates, and demand.

Alternative route from Seattle (SEA) to Denver (DEN)

• Seattle to Colorado Springs (SEA-COS): Colorado Springs Airport (COS) is located approximately 73 miles from Denver International Airport (DEN). One-way economy ticket prices on this route generally fall between $80 and $360, influenced by the time of year and how far in advance you book. Travelers can choose from one-stop and multi-stop flights, with common layover points at both Denver International Airport (DEN) and Salt Lake City International Airport (SLC). Major airlines operating on this route include United and low-cost carrier Southwest Airlines. Additionally, premium service is offered for those seeking first class on this journey.

How to find the best prices for flights from Seattle (SEA) to Denver (DEN)

Getting some of the best deals on flights from Seattle to Denver is all about timing and flexibility. Here are some key tips to help you save:

1. Best times to book and fly: cheaper fares are typically found when booking 2-8 weeks in advance, coinciding with when most travelers make their reservations. Departures in the afternoon (12 PM-6 PM) usually offer lower prices and are also the most popular times to fly. Additionally, flying on Friday provides both better prices and is the most favored travel day.
2. Set up price alerts: stay updated on price changes by using Expedia's Price Tracker. Receive alerts when fares drop for your selected route.
3. Bundle and save: bundle your flight and hotel to save on Expedia, or unlock a hotel deal after booking your flight.*
4. Compare flight options: use Expedia's search tool to compare airlines, routes, direct vs. non-direct flights, and flight times. You can also sort by price to find the most affordable options.
5. Stay flexible with dates: being open to different travel days can sometimes help you find better prices on flights and hotels.
6. Think about luggage: nowadays, it's important to check the airline's baggage policies to find the best value. That may be paying for an additional carry-on bag or booking a ticket with checked luggage included. Either way, double-check your allowance before confirming your booking to avoid excess baggage fees at the airport.

*Members only. Savings vary and are not available on all bundles. Select hotels.

Arriving at Denver International Airport from Seattle - Tacoma International Airport

Denver welcomes travelers from Seattle with a range of transport options based on price, convenience, and proximity. For departures, Seattle - Tacoma International Airport is roughly a 20-minute drive (covering about 14 miles) from central Seattle. Here's how to reach Denver efficiently:

• Hotel transfer: Transfers offer a convenient way to reach your hotel in Denver, with private rides that can be arranged in advance.
• Car rental: Renting a car from Denver International Airport is a great option if you plan to explore and sightsee beyond the city. Browse cheap car rentals at Denver International Airport on Expedia.
• Taxi/ride-hailing: Taxis and ride-hailing services may be available from designated pickup areas outside the terminal, check locally on arrival.
• Public transportation: From Denver International Airport, Jeppesen Terminal Station, a metro station, is located about 0.1 miles away on foot, making it easily accessible for travelers looking to use public transport.

Seattle to Denver Flights

The cheapest times to fly from Seattle to Denver

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 Seattle to Denver are during the month of February. You can find some of the cheapest flights from Seattle to Denver with Expedia's search tool and vast selection of airlines.

The best time to book a flight from Seattle to Denver

Sunday is one of the best days to book for cheap flights from Seattle to Denver: 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 Seattle to Denver

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 Seattle to Denver in 2026. You can also book with separate airlines for your outbound and return journeys, from $69 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 Seattle to Denver 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. Bundling together your Seattle to Denver 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.