FlightRecord

Houston (IAH) to Philadelphia (PHL): On-Time Performance

Data through May 2026

The calendar drives reliability on IAH–PHL. February 2026 flights landed on schedule 91% of the time, but July 2024 dropped to 56% — a gap of 35 points. Across the full period the route averages 79% on-time against a national 78%. Morning departures also hold up better than evening ones (88% vs 71%), which matters most in the rough months.

On-time
79%
arrived <15 min late
Avg delay
24 min
completed flights
Cancelled
2.5%
Flights/day
4.9
last 12 months
Duration
3h 20m
scheduled
Distance
1,325 mi

Best airline from IAH to PHL

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

AirlineOn-timeAvg delayCancelledFlights
United Airlinesmost reliable82%14 min1.3%1,824
American Airlines78%34 min4.0%1,301
Spirit Airlines72%28 min3.9%357
PSA Airlines72%44 min2.1%190

Monthly on-time trend

Monthly on-time percentage for IAH to PHL flights50%75%100%June 2024: 70% on-time (216 flights)70Jun 2024July 2024: 56% on-time (226 flights)56August 2024: 67% on-time (231 flights)67September 2024: 90% on-time (174 flights)90Sep 2024October 2024: 91% on-time (174 flights)91November 2024: 89% on-time (140 flights)89December 2024: 82% on-time (163 flights)82Dec 2024January 2025: 90% on-time (104 flights)90February 2025: 83% on-time (104 flights)83March 2025: 80% on-time (123 flights)80Mar 2025April 2025: 78% on-time (131 flights)78May 2025: 76% on-time (148 flights)76June 2025: 68% on-time (160 flights)68Jun 2025July 2025: 64% on-time (152 flights)64August 2025: 74% on-time (143 flights)74September 2025: 87% on-time (137 flights)87Sep 2025October 2025: 78% on-time (161 flights)78November 2025: 83% on-time (150 flights)83December 2025: 86% on-time (157 flights)86Dec 2025January 2026: 87% on-time (145 flights)87February 2026: 91% on-time (127 flights)91March 2026: 79% on-time (147 flights)79Mar 2026April 2026: 87% on-time (159 flights)87May 2026: 81% on-time (167 flights)81

Best time to fly from IAH to PHL

Aim for departures around 5 a.m. (90% on-time); avoid 7 p.m. departures (53%).

On-time percentage by scheduled departure hour, IAH to PHL5 a.m.: 90% on-time (102 flights)56 a.m.: 88% on-time (226 flights)67 a.m.: 90% on-time (798 flights)78 a.m.: 90% on-time (368 flights)810 a.m.: 81% on-time (27 flights)1011 a.m.: 70% on-time (86 flights)1112 p.m.: 76% on-time (643 flights)121 p.m.: 72% on-time (311 flights)132 p.m.: 65% on-time (239 flights)143 p.m.: 64% on-time (56 flights)154 p.m.: 71% on-time (34 flights)166 p.m.: 75% on-time (707 flights)187 p.m.: 53% on-time (79 flights)198 p.m.: 54% on-time (58 flights)20scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday75%28 min
Tuesdaybest84%17 min
Wednesday81%21 min
Thursday80%17 min
Friday78%23 min
Saturday78%30 min
Sunday77%30 min

What causes delays on this route

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

  • Late-arriving aircraft38%
  • Airline operations43%
  • National airspace system14%
  • Weather5%

Frequently asked questions

How often are flights from IAH to PHL delayed?
21% of IAH–PHL 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 24 minutes.
Which airline is most reliable from IAH to PHL?
United Airlines has the best on-time record on this route at 82%, based on 1,824 flights. 4 airlines flew IAH–PHL frequently enough to compare in this period.
What is the best time of day to fly from IAH to PHL?
Departures around 5 a.m. have the best record (90% on-time), while departures around 7 p.m. have the worst (53%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from IAH to PHL?
The scheduled IAH–PHL flight time averages 3h 20m over 1,325 miles. Actual arrival times vary — flights on this route land 15+ minutes late 21% of the time.
How often are IAH to PHL flights cancelled?
2.5% 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 PHL?
July 2024 was the roughest month in this dataset, with only 56% of arrivals on time. The best was February 2026 at 91%. If your dates are flexible, that 35-point gap is worth planning around.

Based on 3,739 flights, 2024-062026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.