ATL to IAH flight delays & on-time performance
Nonstop flights from Hartsfield Jackson Atlanta International Airport to George Bush Intercontinental Airport · 689 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at ATL or IAH right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Atlanta (ATL) to Houston (IAH) arrived on time 76% of the time in Aug 2025 – Jul 2026, worse than the 78% national average.
- 1.8% were cancelled, and 9% arrived an hour or more late.
- United Airlines was the most punctual airline here (85% on time); Spirit Airlines was the least (66%).
- Departures scheduled around 11am did best (88% on time); around 6pm did worst (60%).
- Wednesday was the most reliable day to fly (82% on time) and Sunday the least (71%).
- The largest source of delay minutes was airline (crew, maintenance, cleaning, fueling) (39%).
Which airline is most on time from ATL 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 | 85% | 0.8% | 12 min | 5.7% | 1,261 |
| Delta Air Lines | 76% | 1.9% | 15 min | 7.7% | 2,521 |
| SkyWest AirlinesRegional airline operating flights for United Express, Delta Connection, American Eagle and Alaska. | 75% | 0.0% | 12 min | 0.0% | 4 |
| Frontier Airlines | 70% | 1.9% | 25 min | 13.8% | 798 |
| Spirit Airlines | 66% | 5.0% | 28 min | 16.4% | 342 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 6am83%140 flights
- 7am83%659 flights
- 8am85%138 flights
- 9am81%375 flights
- 10am82%157 flights
- 11am88%421 flights
- 12pm83%220 flights
- 1pm84%184 flights
- 2pm70%230 flights
- 3pm76%475 flights
- 4pm66%303 flights
- 5pm65%85 flights
- 6pm60%252 flights
- 7pm81%381 flights
- 8pm63%175 flights
- 9pm62%360 flights
- 10pm74%369 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday74%1.9% cancelled
- Tuesday80%1.2% cancelled
- Wednesday82%0.9% cancelled
- Thursday78%0.7% cancelled
- Friday76%1.9% cancelled
- Saturday75%2.8% cancelled
- Sunday71%3.8% 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)39%
- Late-arriving aircraft34%
- Air traffic control & airport congestion24%
- Extreme weather3%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Airline (crew, maintenance, cleaning, fueling)58%
- Extreme weather40%
- Air traffic control & airport congestion2%
- Security0%
ATL to IAH: common questions
- How often are ATL to IAH flights on time?
- 76% 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 Atlanta to Houston cancelled?
- 1.8% of scheduled flights were cancelled (91 of 4,926).
- How long are typical delays?
- Across all flights the average arrival delay was 17 min (early arrivals count as zero). Flights that were late arrived 66 min behind schedule on average, and 8.7% of flights were an hour or more late.
- How long is taxi time at ATL?
- Flights on this route spent 19 min taxiing from the gate to takeoff on average.
Related routes
Return trip: IAH to ATL — 77% on time
More flights from Atlanta
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: ATL → IAH, nonstop flights by US airlines that report to the DOT. How we calculate this.