Cheap flights from Seattle to Denver (SEA to DEN) from $210

Book at the right time: For domestic routes like Seattle to Denver, the sweet spot is 3–5 weeks before departure. Booking too early can mean missing seat sales; too late means paying peak prices.

Shift your dates by a day or two: Mid-week departures (Tuesday–Wednesday) are almost always cheaper than weekend flights. Even shifting by one day can make a meaningful difference.

Direct flights are available: Direct flights take around 7h 9m and are worth it for convenience — but check if a one-stop flight is significantly cheaper before ruling it out.

Factor in baggage fees: Low-cost carriers on this route often advertise attractive base fares but charge separately for checked luggage. Always compare the all-in price — a $20 cheaper fare plus $50 baggage fee is no saving. Alaska Airlines and American Airlines may have different inclusions, so check each airline's fare conditions.

Search in private browsing: Some booking sites use cookies to track repeat searches and may show higher prices after multiple lookups. Use an incognito or private window — or just use Booked AI, which pulls live prices without any tracking markup.

The cheapest flights from Seattle to Denver start from $210, with typical prices ranging from $210 to $396.

The typical flight time from Seattle to Denver is approximately 7 hours and 9 minutes. Direct flights are available on this route.

Airlines operating this route include Alaska Airlines, American Airlines, Frontier Airlines, Hawaiian Airlines.