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

Atlanta, GA (ATL) to Seattle, WA (SEA) flight delay odds

77.1% of 3,277 official scheduled ATL-to-SEA flights arrived on time; 12.1% arrived at least 30 minutes late and 0.6% 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
77.1%arrived on time
12.1%30+ min late
0.6%cancelled
3,277scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late5.2%all scheduled flights
120+ minutes late2.0%all scheduled flights
Diverted0.3%did not reach as scheduled
Average arrival+4.4 mincompleted flights

Which departure time was most reliable for ATL to SEA?

Among qualifying ATL-to-SEA departure window results, Early morning had the highest on-time rate: 81.8% of 726 flights. Evening was lowest at 64.2% across 651 flights.

Departure windowFlightsOn time30+ minCancelled
Early morning72681.8%9.0%1.1%
Late morning84680.7%9.8%0.4%
Afternoon78978.7%11.4%0.1%
Evening65164.2%20.0%1.1%
Night26578.9%10.6%0.8%

Which weekday was most reliable for ATL to SEA?

Among qualifying ATL-to-SEA weekday results, Saturday had the highest on-time rate: 81.0% of 452 flights. Monday was lowest at 73.8% across 481 flights.

DayFlightsOn time30+ minCancelled
Monday48173.8%12.5%0.8%
Tuesday46377.5%10.8%0.4%
Wednesday44578.0%12.6%0.2%
Thursday47679.0%12.0%0.6%
Friday47774.6%13.0%0.4%
Saturday45281.0%10.6%1.1%
Sunday48375.8%13.0%0.8%

Which airline was most reliable for ATL to SEA?

Among qualifying ATL-to-SEA airline results, Delta Air Lines had the highest on-time rate: 78.5% of 2,371 flights. Alaska Airlines was lowest at 73.3% across 906 flights.

AirlineFlightsOn time30+ minCancelled
Delta Air Lines2,37178.5%11.3%0.5%
Alaska Airlines90673.3%14.2%1.1%

Which month was most reliable for ATL to SEA?

Among qualifying ATL-to-SEA month results, September 2025 had the highest on-time rate: 89.0% of 283 flights. December 2025 was lowest at 60.2% across 269 flights.

MonthFlightsOn time30+ minCancelled
July 202534776.7%13.0%0.9%
August 202531576.2%15.9%0.3%
September 202528389.0%5.7%0.0%
October 202529580.7%11.5%1.0%
November 202525784.0%8.6%0.8%
December 202526960.2%20.1%1.1%
January 202621472.4%13.6%1.4%
February 202619374.6%9.3%0.5%
March 202623267.7%18.1%1.3%
April 202625287.7%6.7%0.4%
May 202629676.7%11.8%0.0%
June 202632476.2%10.5%0.3%

What drove ATL to SEA delay minutes?

Airline was the largest recorded ATL-to-SEA delay category, accounting for 49.9% of 38,746 BTS-attributed delay minutes during July 2025–June 2026.

Airline49.9%
Late aircraft18.7%
National airspace26.8%
Weather4.5%
Security0.1%
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.