FlightRecord

Houston (IAH) to Atlanta (ATL): On-Time Performance

Data through May 2026

The calendar drives reliability on IAH–ATL. September 2025 flights landed on schedule 91% of the time, but July 2024 dropped to 58% — a gap of 33 points. Across the full period the route averages 77% on-time against a national 78%. Morning departures also hold up better than evening ones (83% vs 68%), which matters most in the rough months.

On-time
77%
arrived <15 min late
Avg delay
18 min
completed flights
Cancelled
2.1%
Flights/day
13
last 12 months
Duration
2h 7m
scheduled
Distance
689 mi

Best airline from IAH to ATL

5 airlines flew this route regularly between 2024-06 and 2026-05.

AirlineOn-timeAvg delayCancelledFlights
SkyWest Airlinesmost reliable87%10 min0.0%115
Delta Air Lines81%15 min2.0%4,790
United Airlines78%17 min1.3%2,171
Spirit Airlines73%17 min3.3%1,110
Frontier Airlines59%34 min2.8%1,240

Monthly on-time trend

Monthly on-time percentage for IAH to ATL flights50%75%100%June 2024: 71% on-time (399 flights)71Jun 2024July 2024: 58% on-time (386 flights)58August 2024: 79% on-time (418 flights)79September 2024: 81% on-time (381 flights)81Sep 2024October 2024: 86% on-time (422 flights)86November 2024: 83% on-time (402 flights)83December 2024: 74% on-time (375 flights)74Dec 2024January 2025: 80% on-time (323 flights)80February 2025: 81% on-time (316 flights)81March 2025: 78% on-time (366 flights)78Mar 2025April 2025: 77% on-time (343 flights)77May 2025: 69% on-time (395 flights)69June 2025: 63% on-time (390 flights)63Jun 2025July 2025: 72% on-time (413 flights)72August 2025: 80% on-time (379 flights)80September 2025: 91% on-time (384 flights)91Sep 2025October 2025: 80% on-time (438 flights)80November 2025: 80% on-time (401 flights)80December 2025: 78% on-time (367 flights)78Dec 2025January 2026: 81% on-time (395 flights)81February 2026: 86% on-time (381 flights)86March 2026: 66% on-time (440 flights)66Mar 2026April 2026: 79% on-time (466 flights)79May 2026: 70% on-time (446 flights)70

Best time to fly from IAH to ATL

Aim for departures around 7 a.m. (88% on-time); avoid 9 p.m. departures (57%).

On-time percentage by scheduled departure hour, IAH to ATL5 a.m.: 86% on-time (528 flights)56 a.m.: 81% on-time (807 flights)67 a.m.: 88% on-time (1,384 flights)78 a.m.: 82% on-time (195 flights)89 a.m.: 82% on-time (632 flights)910 a.m.: 69% on-time (114 flights)1011 a.m.: 79% on-time (767 flights)1112 p.m.: 78% on-time (549 flights)121 p.m.: 73% on-time (355 flights)132 p.m.: 76% on-time (834 flights)143 p.m.: 73% on-time (422 flights)154 p.m.: 65% on-time (510 flights)165 p.m.: 65% on-time (466 flights)176 p.m.: 69% on-time (1,188 flights)187 p.m.: 63% on-time (218 flights)198 p.m.: 74% on-time (395 flights)209 p.m.: 57% on-time (42 flights)21scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday75%20 min
Tuesday79%16 min
Wednesdaybest81%17 min
Thursday77%18 min
Friday77%18 min
Saturday77%17 min
Sunday72%21 min

What causes delays on this route

Share of total delay minutes by cause, as reported by carriers to the US DOT.

  • Late-arriving aircraft43%
  • Airline operations31%
  • National airspace system23%
  • Weather3%

Frequently asked questions

How often are flights from IAH to ATL delayed?
23% of IAH–ATL flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 18 minutes.
Which airline is most reliable from IAH to ATL?
SkyWest Airlines has the best on-time record on this route at 87%, based on 115 flights. 5 airlines flew IAH–ATL frequently enough to compare in this period.
What is the best time of day to fly from IAH to ATL?
Departures around 7 a.m. have the best record (88% on-time), while departures around 9 p.m. have the worst (57%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from IAH to ATL?
The scheduled IAH–ATL flight time averages 2h 7m over 689 miles. Actual arrival times vary — flights on this route land 15+ minutes late 23% of the time.
How often are IAH to ATL flights cancelled?
2.1% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, slightly above the national rate of 1.6%.
What is the worst month to fly from IAH to ATL?
July 2024 was the roughest month in this dataset, with only 58% of arrivals on time. The best was September 2025 at 91%. If your dates are flexible, that 33-point gap is worth planning around.

Based on 9,426 flights, 2024-062026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.