Cheap flights from Washington to Seattle from $346 DCA, IAD → SEA
Ronald Reagan National Airport (DCA), Washington Dulles International Airport (IAD) → Seattle-Tacoma International Airport (SEA)
The cheapest return found recently is $346 with Frontier Airlines, 22 Jan 2027 – 25 Jan 2027, found today.
- Cheapest return found recently
- $346, 22 Jan 2027 to 25 Jan 2027
- Usual return price
- $370 to $437
- Cheapest month to fly
- January 2027, return fares from $346 found in the last 7 days
- Airlines with nonstop flights
- Alaska Airlines
Return
The cheapest return fare on each of 4 departure dates is usually $370 to $437.
Cheapest return found recently
$346
22 Jan 2027 – 25 Jan 2027 · Frontier Airlines
Ronald Reagan National Airport (DCA) → Seattle-Tacoma International Airport (SEA)
Leaves 1:30 p.m. · Return leaves 1:33 p.m. · 51 h 1 min of travel, both ways together
out 1 stop, back 1 stop
found today
Cheapest nonstop return
$425
6 Feb 2027 – 15 Feb 2027 · Alaska Airlines
Washington Dulles International Airport (IAD) → Seattle-Tacoma International Airport (SEA)
Leaves 5:30 p.m. · Return leaves 9:55 p.m. · 10 h 52 min of travel, both ways together
out nonstop, back nonstop
found yesterday
Found recently, and the cheapest we hold
$346 22 Jan 2027 – 25 Jan 2027found todaySee prices for these dates
It is also the cheapest return we hold, of any age.
What have prices looked like?
Over 50 days, 24 Sept to 12 Nov, the cheapest return we saw each day was $279 to $455.
Those were the prices on those days, not today's.
Is this a good return price?
Compared with the cheapest return fare on each of 4 departure dates from 25 Dec to 6 Feb 2027, found by travelers' searches in the last 7 days (economy, the price the seller showed on Aviasales). The usual range is the middle half of those prices.
Could nearby dates be cheaper?
We hold no other 3-night return fares leaving within 3 days of 22 Jan 2027 to compare.
Every date we hold
45 fares on 4 departure dates
See the chart as a table
| Dates | From | Airline | Airports | Stops | Found | |
|---|---|---|---|---|---|---|
| 25 Dec – 28 Dec | $407 | Alaska Airlines | Washington Dulles International Airport (IAD) → Seattle-Tacoma International Airport (SEA) | out nonstop, back 1 stop | found 4 hours ago | See prices for these dates |
| 29 Dec – 31 Dec | $528 | Alaska Airlines | Washington Dulles International Airport (IAD) → Seattle-Tacoma International Airport (SEA) | out nonstop, back nonstop | found today | See prices for these dates |
| 22 Jan 2027 – 25 Jan 2027 | $346 | Frontier Airlines | Ronald Reagan National Airport (DCA) → Seattle-Tacoma International Airport (SEA) | out 1 stop, back 1 stop | found today | See prices for these dates |
| 6 Feb 2027 – 15 Feb 2027 | $378 | Frontier Airlines | Ronald Reagan National Airport (DCA) → Seattle-Tacoma International Airport (SEA) | out 1 stop, back 1 stop | found yesterday | See prices for these dates |
Which month looks cheapest?
January 2027 is the cheapest month — from $346.
Airlines on the cheapest dates: Alaska Airlines, Frontier Airlines.
Premium cabin fares from Washington to Seattle
We hold no premium economy, business or first-class fares for this route: we collect them for the busiest routes, and this one is not among them yet.
Today's prices for 22 Jan 2027 – 25 Jan 2027 in another cabin: Premium economy · Business · First
How far ahead were prices cheapest for Washington to Seattle?
Return
The cheapest fares were 14 to 29 days before departure.
From the cheapest return each day between 24 Sept and 12 Nov (50 days), grouped by how many days ahead the flight left; one adult in economy.
Each range covers different departure dates, so this compares typical fares, not the same trip priced twice.
Prices reflect recent searches — current fares may differ.
See these ranges as a table
| Booked ahead by | Typical fare | Cheapest day | Above the cheapest | Days of prices |
|---|---|---|---|---|
| 14–29 days | $279 | $279 | Cheapest seen | 12 |
| 30–59 days | $380 | $368 | +36% | 12 |
| 60–89 days | $419 | $411 | +50% | 8 |
| 90–179 days | $437 | $374 | +57% | 46 |
Could a nearby airport be cheaper?
A different airport at either end can change the fare — sometimes a lot.
Return
Baltimore → Seattle
57 km from Washington
$396
$50 more than flying from Washington
22 Jan 2027 – 25 Jan 2027 · BWI → SEA · out nonstop, back 1 stop
found today
Cheapest recent price on each route — round trip, per traveler in Economy. Distances are in a straight line.
One-way
Baltimore → Seattle
57 km from Washington
$244
30 Jun 2027 · BWI → SEA · 1 stop
found yesterday
Cheapest recent price on each route — one way, per traveler in Economy. Distances are in a straight line.
Live price for these dates
The cheapest return found recently is for 22 Jan 2027 – 25 Jan 2027. A live search on this page shows what those dates cost now, for one adult in economy.
Questions about this trip
How much is a return flight from Washington to Seattle?
The cheapest return found recently is $346 with Frontier Airlines, 22 Jan 2027 to 25 Jan 2027, found today. The cheapest return fare on each of 4 departure dates is usually $370 to $437.
What is the cheapest month to fly from Washington to Seattle?
January 2027 is the cheapest month for a return, from $346, 22 Jan 2027 to 25 Jan 2027, found today.
How far ahead should I book a flight from Washington to Seattle?
In 50 days of prices between 24 Sept and 12 Nov, return fares were cheapest 14 to 29 days before departure.
Is there a direct flight from Washington to Seattle?
Yes, the cheapest nonstop return found recently is $425 with Alaska Airlines, 6 Feb 2027 to 15 Feb 2027, found yesterday.
Which airlines have the cheapest flights from Washington to Seattle?
Between 25 Dec and 6 Feb 2027, Alaska Airlines has the cheapest return on 2 of the 4 departure dates we hold, and Frontier Airlines on 2.
Prices are what travelers' searches on Aviasales found in the last 7 days, in US dollars: the price the seller showed on Aviasales; bags may cost extra. Fares change, so check today's price before you book. How our prices work