SEA to IAH flight delays & on-time performance
Nonstop flights from Seattle–Tacoma International Airport to George Bush Intercontinental Airport · 1,874 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at SEA or IAH right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Seattle (SEA) to Houston (IAH) arrived on time 82% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 0.4% were cancelled, and 4% arrived an hour or more late.
- United Airlines was the most punctual airline here (86% on time); Alaska Airlines was the least (76%).
- Departures scheduled around 6am did best (93% on time); around 11am did worst (65%).
- Wednesday was the most reliable day to fly (86% on time) and Friday the least (78%).
- The largest source of delay minutes was airline (crew, maintenance, cleaning, fueling) (47%).
Which airline is most on time from SEA to IAH?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| United Airlines | 86% | 0.3% | 11 min | 3.7% | 1,238 |
| Alaska Airlines | 76% | 0.6% | 12 min | 3.9% | 852 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 5am87%94 flights
- 6am93%101 flights
- 7am90%263 flights
- 9am89%56 flights
- 10am79%181 flights
- 11am65%229 flights
- 12pm83%93 flights
- 1pm84%124 flights
- 2pm78%45 flights
- 4pm78%23 flights
- 5pm84%394 flights
- 10pm91%23 flights
- 11pm82%463 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday84%0.7% cancelled
- Tuesday84%0.4% cancelled
- Wednesday86%0.7% cancelled
- Thursday81%0.3% cancelled
- Friday78%0.3% cancelled
- Saturday82%0.3% cancelled
- Sunday83%0.3% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Airline (crew, maintenance, cleaning, fueling)47%
- Late-arriving aircraft30%
- Air traffic control & airport congestion21%
- Extreme weather1%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Airline (crew, maintenance, cleaning, fueling)67%
- Extreme weather33%
- Air traffic control & airport congestion0%
- Security0%
SEA to IAH: common questions
- How often are SEA to IAH flights on time?
- 82% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from Seattle to Houston cancelled?
- 0.4% of scheduled flights were cancelled (9 of 2,090).
- How long are typical delays?
- Across all flights the average arrival delay was 12 min (early arrivals count as zero). Flights that were late arrived 61 min behind schedule on average, and 3.8% of flights were an hour or more late.
- How long is taxi time at SEA?
- Flights on this route spent 20 min taxiing from the gate to takeoff on average.
Related routes
Return trip: IAH to SEA — 79% on time
More flights from Seattle
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: SEA → IAH, nonstop flights by US airlines that report to the DOT. How we calculate this.