Cheap flights from Seattle to Denver from C$ 137

In general, January is the cheapest month to fly from Seattle to Denver. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around C$ 223. If you aren’t able to travel during the month of January, then book flights to Denver from Seattle during February instead. Flights to Denver in February, while not as cheap as those in January, still average around C$ 280.

The cheapest day to depart from Seattle to Denver is on a Thursday. Travellers who choose to depart for Denver on a Thursday will often find tickets for as low as C$ 280. On the other hand, Sunday is the most expensive day to depart from Seattle because it is more convenient for both business and leisure travellers. As a result, prices tend to be around C$ 510.

Our most recent data shows that the best time of day to fly to Denver is in the afternoon. Flights from Seattle to Denver during this time can be as low as C$ 304. Try not to purchase tickets at noon because they tend to be around C$ 382. Of course, these prices can vary depending on the time of year and what airport you fly to.

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

You are more likely to see cheaper flights to Denver from Seattle when booking weeks ahead of your departure date. In general, you can expect to find flights to Denver for around C$ 349 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Denver from Seattle for as low as C$ 292 on momondo.

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

No. A direct flight is the cheapest option for a flight between Seattle to Denver.

As of September 2026, prices for Seattle to Denver flights are approximately 28% cheaper when compared to flights at the same time last year.

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

Frontier, Southwest and Alaska Airlines are the top three most popular airlines that fly to Denver from Seattle according to our data. Frontier is the first choice among our users, with 66% of people opting to fly with this airline when travelling to Denver. Keep in mind that there are 4 different airlines that fly to Denver on a routine basis, so you have a few additional options to choose from.

Historically, on average around 17% of flights between Seattle and Denver have experienced a delay on any given week. The average delay length over the past 12 months has been 138 minutes.

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

Saturday is statistically the day of the week that experiences the fewest delays on this flight route. Friday has historically seen more delays on average compared to the rest of the week.

According to our data, United Airlines has had the least delays on this route over the last 12 months, with about 8% of their flights experiencing any sort of delay.

As of September 2026, 15 flights take off from Seattle and land in Denver each day. The most common flight departure time for this route is 1:00p.m., with 41% of daily flights taking off in the afternoon.

The number of flights available between Seattle and Denver is 110 per week as of September 2026. The most frequent departure day is Mon, with 37% of weekly flights leaving on this day.