Cheap flights from Denver to Seattle from $89

In general, January is the cheapest month to fly from Denver to Seattle. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $138. If you don’t want to visit Seattle in January, then you should wait until February to fly from Denver, when ticket prices are also cheap, with an average price of $174.

On average, the least expensive day to fly to Seattle from Denver is on a Friday. momondo users have found tickets for Friday departures for as low as $296. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Tuesday is the most expensive day to depart from Denver because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $388.

Flying to Seattle from Denver in the morning is the least expensive time of day to depart. momondo users have found prices as low as $316 when looking at flights departing in the morning. Flights to Seattle are more costly in the afternoon, with an average ticket price of $397. Departure times in the afternoon fall within the peak daily travel times, which is why tickets can be more expensive.

Fly from Denver Intl to Seattle/Tacoma Intl for the best Denver Intl - Seattle/Tacoma Intl flight prices

You are more likely to see cheaper flights to Seattle from Denver when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around $238 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from Denver for as low as $208 on momondo.

There are 4 cabin classes available to choose from on Denver to Seattle flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Alaska Airlines, Delta, and Southwest are the most popular carriers operating from Denver Intl to Seattle/Tacoma Intl

Frontier, Alaska Airlines and United Airlines are the top three most popular airlines that fly to Seattle from Denver according to our data. Frontier is the first choice among our users, with 42% of people opting to fly with this airline when traveling to Seattle. Keep in mind that there are 5 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.

Historically, on average around 17% of flights between Denver and Seattle have experienced a delay on any given week. The average delay length over the past 12 months has been 141 minutes.

Generally, flights departing in the morning tend to experience fewer delays. Flights at night have, in the past, seen delays more frequently in comparison.

Tuesday is statistically the day of the week which experiences the fewest number of delays on this flight route. Thursday has historically seen more delays on average compared to the rest of the week.

According to our data, Frontier have had the least number of delays on this route over the last 12 months; with about 11% of their flights experiencing any sort of delay.

20 flights are operational daily from Denver to Seattle as of September 2026. The most popular departure time for this route is 1:00PM, with 46% of flights per day taking off in the afternoon.

145 flights are operational weekly from Denver to Seattle as of September 2026. The most popular departure day for this route is Mon, with 32% of flights per week taking off on this day.