BTS DATA COMPLETE THROUGH JUNE 2026HISTORICAL ODDS · NOT LIVE FLIGHT STATUS
DelayOddsKnow the route before you book
SEA→DCA

Seattle, WA (SEA) to Washington, DC (DCA) flight delay odds

79.3% of 1,094 official scheduled SEA-to-DCA flights arrived on time; 12.4% arrived at least 30 minutes late and 1.7% were cancelled during July 2025–June 2026.

Source: U.S. Bureau of Transportation Statistics · Reporting window: July 2025–June 2026 · Updated September 16, 2026

HISTORICAL ROUTE SIGNALGenerally reliable
79.3%arrived on time
12.4%30+ min late
1.7%cancelled
1,094scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late6.0%all scheduled flights
120+ minutes late2.3%all scheduled flights
Diverted1.2%did not reach as scheduled
Average arrival-1.0 mincompleted flights

Which departure time was most reliable for SEA to DCA?

Among qualifying SEA-to-DCA departure window results, Early morning had the highest on-time rate: 86.2% of 730 flights. Afternoon was lowest at 65.4% across 364 flights.

Departure windowFlightsOn time30+ minCancelled
Early morning73086.2%7.1%2.1%
Afternoon36465.4%23.1%1.1%

Which weekday was most reliable for SEA to DCA?

Among qualifying SEA-to-DCA weekday results, Saturday had the highest on-time rate: 87.8% of 156 flights. Thursday was lowest at 73.5% across 155 flights.

DayFlightsOn time30+ minCancelled
Monday15675.0%15.4%1.9%
Tuesday15982.4%8.8%1.9%
Wednesday15683.3%9.6%0.6%
Thursday15573.5%20.6%1.3%
Friday15677.6%11.5%1.3%
Saturday15687.8%5.8%1.3%
Sunday15675.0%15.4%3.8%

Which airline was most reliable for SEA to DCA?

Among qualifying SEA-to-DCA airline results, Delta Air Lines had the highest on-time rate: 89.0% of 365 flights. Alaska Airlines was lowest at 74.3% across 729 flights.

AirlineFlightsOn time30+ minCancelled
Alaska Airlines72974.3%15.9%1.1%
Delta Air Lines36589.0%5.5%3.0%

Which month was most reliable for SEA to DCA?

Among qualifying SEA-to-DCA month results, May 2026 had the highest on-time rate: 91.4% of 93 flights. July 2025 was lowest at 61.3% across 93 flights.

MonthFlightsOn time30+ minCancelled
July 20259361.3%18.3%4.3%
August 20259375.3%16.1%2.2%
September 20259063.3%20.0%0.0%
October 20259387.1%9.7%0.0%
November 20258976.4%16.9%0.0%
December 20259382.8%8.6%2.2%
January 20269377.4%14.0%5.4%
February 20268479.8%16.7%1.2%
March 20269381.7%9.7%4.3%
April 20269091.1%4.4%0.0%
May 20269391.4%6.5%0.0%
June 20269083.3%8.9%1.1%

What drove SEA to DCA delay minutes?

National airspace was the largest recorded SEA-to-DCA delay category, accounting for 45.0% of 13,204 BTS-attributed delay minutes during July 2025–June 2026.

Airline37.0%
Late aircraft10.0%
National airspace45.0%
Weather7.5%
Security0.5%
This is historical evidence, not a forecast.

Weather, schedules and operations change. For a trip you have already booked, use the airline or airport for live status.