Cheap flights from Washington, D.C. to Seattle from $166

In general, February is the cheapest month to fly from Washington, D.C. to Seattle. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $282. If you don’t want to visit Seattle in February, then you should wait until January to fly from Washington, D.C., when ticket prices are also cheap, with an average price of $283.

On average, the least expensive day to fly to Seattle from Washington, D.C. is on a Wednesday. momondo users have found tickets for Wednesday departures for as low as $458. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Sunday is the most expensive day to depart from Washington, D.C. because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $591.

Flying to Seattle from Washington, D.C. in the afternoon is the least expensive time of day to depart. momondo users have found prices as low as $485 when looking at flights departing in the afternoon. Flights to Seattle are more costly in the evening, with an average ticket price of $646. Departure times in the evening fall within the peak daily travel times, which is why tickets can be more expensive.

Fly from Washington, D.C. Dulles Intl to Seattle/Tacoma Intl for the best Washington, D.C. - Seattle/Tacoma Intl flight prices

You are more likely to see cheaper flights to Seattle from Washington, D.C. when booking weeks ahead of your departure date. In general, you can expect to find flights to Seattle for around $392 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Seattle from Washington, D.C. for as low as $353 on momondo.

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

You could potentially save up to 19% on your flight if you consider stops on a Washington, D.C. to Seattle flight.

As of August 2026, prices for Washington, D.C. to Seattle flights are approximately 18% cheaper when compared to flights at the same time last year.

Alaska Airlines, Southwest, and United Airlines are the most popular carriers operating from Washington, D.C. to Seattle/Tacoma Intl

Alaska Airlines, United Airlines and Delta are the top three most popular airlines that fly to Seattle from Washington, D.C. according to our data. Alaska Airlines is the first choice among our users, with 59% of people opting to fly with this airline when traveling to Seattle. Keep in mind that there are 8 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.

Denver (DEN) was the most common stop: 54% of momondo users choosing 1-stop flights on this route connected there.

Flights via Minneapolis (MSP) offer the lowest average round-trip price of $211.

Flights connecting via Minneapolis (MSP) have the shortest average one-way travel time: 7h 38m.

Charlotte (CLT) has the shortest average layover time for this route: 1h 27m.

As of August 2026, 18 flights take off from Washington, D.C. and land in Seattle each day. The most common flight departure time for this route is 5:00PM, with 53% of daily flights taking off at noon.

As of August 2026, there are 129 flights per week flying from Washington, D.C. to Seattle. The most common day of the week flights depart is Mon, with 28% of flights taking off on this day.