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

Houston, TX (IAH) to Seattle, WA (SEA) flight delay odds

76.9% of 2,095 official scheduled IAH-to-SEA flights arrived on time; 13.6% arrived at least 30 minutes late and 0.5% 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
76.9%arrived on time
13.6%30+ min late
0.5%cancelled
2,095scheduled flights
Based on July 2025–June 2026; on time means arrival less than 15 minutes late.
60+ minutes late6.3%all scheduled flights
120+ minutes late1.9%all scheduled flights
Diverted0.1%did not reach as scheduled
Average arrival+5.2 mincompleted flights

Which departure time was most reliable for IAH to SEA?

Among qualifying IAH-to-SEA departure window results, Early morning had the highest on-time rate: 85.8% of 515 flights. Evening was lowest at 65.6% across 742 flights.

Departure windowFlightsOn time30+ minCancelled
Early morning51585.8%5.6%0.8%
Late morning41581.2%10.8%0.5%
Afternoon40482.2%11.6%0.0%
Evening74265.6%21.7%0.7%

Which weekday was most reliable for IAH to SEA?

Among qualifying IAH-to-SEA weekday results, Tuesday had the highest on-time rate: 81.6% of 288 flights. Saturday was lowest at 73.6% across 296 flights.

DayFlightsOn time30+ minCancelled
Monday30576.4%14.4%0.7%
Tuesday28881.6%11.5%0.0%
Wednesday28176.9%13.2%0.4%
Thursday31079.0%11.6%0.3%
Friday30977.0%12.9%1.0%
Saturday29673.6%16.9%0.0%
Sunday30674.2%14.4%1.3%

Which airline was most reliable for IAH to SEA?

Among qualifying IAH-to-SEA airline results, Alaska Airlines had the highest on-time rate: 77.8% of 852 flights. United Airlines was lowest at 76.3% across 1,243 flights.

AirlineFlightsOn time30+ minCancelled
United Airlines1,24376.3%14.2%0.4%
Alaska Airlines85277.8%12.6%0.7%

Which month was most reliable for IAH to SEA?

Among qualifying IAH-to-SEA month results, April 2026 had the highest on-time rate: 90.7% of 150 flights. July 2025 was lowest at 65.7% across 236 flights.

MonthFlightsOn time30+ minCancelled
July 202523665.7%20.8%1.7%
August 202522868.0%17.5%1.3%
September 202519985.9%7.5%0.0%
October 202517580.0%12.0%0.6%
November 202514877.7%10.1%0.0%
December 202516969.8%16.6%0.0%
January 202613474.6%15.7%0.7%
February 202611282.1%8.9%0.0%
March 202614475.0%16.7%1.4%
April 202615090.7%7.3%0.0%
May 202618388.0%8.2%0.0%
June 202621774.2%16.1%0.0%

What drove IAH to SEA delay minutes?

Late aircraft was the largest recorded IAH-to-SEA delay category, accounting for 41.4% of 25,462 BTS-attributed delay minutes during July 2025–June 2026.

Airline27.6%
Late aircraft41.4%
National airspace24.9%
Weather5.7%
Security0.4%
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.