Flights to Herndon from Seattle - $134

View $134 flight on Tue, Oct 28, 2025Opens in a new window

Popular airlines from Seattle to Herndon

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Cheap Flights from Seattle to Herndon (SEA-WAS)

Prices were available within the past 7 days and start at $134 for one-way flights and $254 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Bargain Flight
Wed, Oct 1 - Wed, Oct 8
SEA
Seattle
IAD
Washington
$254 Roundtrip, found 3 hours ago
$254
Roundtrip
found 3 hours ago
Select Bargain Flight flight, departing Wed, Oct 1 from Seattle to Washington, returning Wed, Oct 8, priced at $254 found 3 hours ago
Bargain Flight
Wed, Oct 1 - Wed, Oct 8
SEA
Seattle
DCA
Washington
$254 Roundtrip, found 4 hours ago
$254
Roundtrip
found 4 hours ago
Select Bargain Flight flight, departing Wed, Oct 1 from Seattle to Washington, returning Wed, Oct 8, priced at $254 found 4 hours ago
United
Tue, Oct 28 - Wed, Nov 5
SEA
Seattle
IAD
Washington
$257 Roundtrip, found 1 hour ago
$257
Roundtrip
found 1 hour ago
Select United flight, departing Tue, Oct 28 from Seattle to Washington, returning Wed, Nov 5, priced at $257 found 1 hour ago
Delta
Tue, Oct 28 - Wed, Nov 5
SEA
Seattle
DCA
Washington
$257 Roundtrip, found 2 hours ago
$257
Roundtrip
found 2 hours ago
Select Delta flight, departing Tue, Oct 28 from Seattle to Washington, returning Wed, Nov 5, priced at $257 found 2 hours ago
Frontier Airlines
Tue, Aug 19 - Tue, Aug 19
SEA
Seattle
DCA
Washington
$263 Roundtrip, found 1 day ago
$263
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Tue, Aug 19 from Seattle to Washington, returning Tue, Aug 19, priced at $263 found 1 day ago
Southwest Airlines
Wed, Oct 1 - Wed, Oct 8
SEA
Seattle
DCA
Washington
$277 Roundtrip, found 4 hours ago
$277
Roundtrip
found 4 hours ago
Select Southwest Airlines flight, departing Wed, Oct 1 from Seattle to Washington, returning Wed, Oct 8, priced at $277 found 4 hours ago

Find the cheapest month to fly from Seattle (SEA) to Washington (DCA)

September is typically the cheapest month to fly

From $138 - $262 per traveler.

Graph displaying average flight prices per month

Alternative airports near Herndon

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Ronald Reagan Washington National DCA. Cheapest option available. Average driving time to city center is 34 minutes. Flights from $288
DCA
Ronald Reagan Washington National
Cheapest
Average driving time to city center34 min
Flights from $288
Select flight to Washington Dulles Intl. IAD. Closest option available. Average driving time to city center is 9 minutes. Flights from $308
IAD
Washington Dulles Intl.
Closest
Average driving time to city center9 min
Flights from $308

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