FlightRecord

Washington (DCA) to Houston (IAH): On-Time Performance

Data through May 2026

The calendar drives reliability on DCA–IAH. October 2024 flights landed on schedule 91% of the time, but July 2024 dropped to 62% — a gap of 29 points. Across the full period the route averages 82% on-time against a national 78%. Morning departures also hold up better than evening ones (90% vs 75%), which matters most in the rough months.

On-time
82%
arrived <15 min late
Avg delay
16 min
completed flights
Cancelled
2.2%
Flights/day
8.5
last 12 months
Duration
3h 30m
scheduled
Distance
1,208 mi

Best airline from DCA to IAH

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

AirlineOn-timeAvg delayCancelledFlights
United Airlinesmost reliable83%16 min1.7%4,586
Republic Airways76%15 min5.1%511
PSA Airlines70%20 min4.1%194

Monthly on-time trend

Monthly on-time percentage for DCA to IAH flights50%75%100%June 2024: 77% on-time (160 flights)77Jun 2024July 2024: 62% on-time (167 flights)62August 2024: 83% on-time (170 flights)83September 2024: 86% on-time (171 flights)86Sep 2024October 2024: 91% on-time (182 flights)91November 2024: 91% on-time (196 flights)91December 2024: 80% on-time (180 flights)80Dec 2024January 2025: 78% on-time (176 flights)78February 2025: 81% on-time (176 flights)81March 2025: 90% on-time (196 flights)90Mar 2025April 2025: 88% on-time (202 flights)88May 2025: 79% on-time (206 flights)79June 2025: 66% on-time (193 flights)66Jun 2025July 2025: 74% on-time (207 flights)74August 2025: 82% on-time (207 flights)82September 2025: 86% on-time (272 flights)86Sep 2025October 2025: 88% on-time (291 flights)88November 2025: 81% on-time (270 flights)81December 2025: 81% on-time (274 flights)81Dec 2025January 2026: 84% on-time (282 flights)84February 2026: 90% on-time (258 flights)90March 2026: 83% on-time (289 flights)83Mar 2026April 2026: 83% on-time (282 flights)83May 2026: 71% on-time (288 flights)71

Best time to fly from DCA to IAH

Aim for departures around 7 a.m. (100% on-time); avoid 4 p.m. departures (63%).

On-time percentage by scheduled departure hour, DCA to IAH6 a.m.: 90% on-time (742 flights)67 a.m.: 100% on-time (30 flights)78 a.m.: 91% on-time (707 flights)811 a.m.: 91% on-time (717 flights)1112 p.m.: 88% on-time (713 flights)121 p.m.: 70% on-time (190 flights)132 p.m.: 77% on-time (646 flights)143 p.m.: 77% on-time (22 flights)154 p.m.: 63% on-time (692 flights)167 p.m.: 75% on-time (712 flights)198 p.m.: 74% on-time (103 flights)20scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday81%16 min
Tuesday86%13 min
Wednesday81%15 min
Thursday80%16 min
Friday80%20 min
Saturdaybest88%11 min
Sunday80%17 min

What causes delays on this route

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

  • Late-arriving aircraft41%
  • Airline operations27%
  • National airspace system27%
  • Weather5%

Frequently asked questions

How often are flights from DCA to IAH delayed?
18% of DCA–IAH 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 16 minutes.
Which airline is most reliable from DCA to IAH?
United Airlines has the best on-time record on this route at 83%, based on 4,586 flights. 3 airlines flew DCA–IAH frequently enough to compare in this period.
What is the best time of day to fly from DCA to IAH?
Departures around 7 a.m. have the best record (100% on-time), while departures around 4 p.m. have the worst (63%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from DCA to IAH?
The scheduled DCA–IAH flight time averages 3h 30m over 1,208 miles. Actual arrival times vary — flights on this route land 15+ minutes late 18% of the time.
How often are DCA to IAH flights cancelled?
2.2% 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 DCA to IAH?
July 2024 was the roughest month in this dataset, with only 62% of arrivals on time. The best was October 2024 at 91%. If your dates are flexible, that 29-point gap is worth planning around.

Based on 5,295 flights, 2024-062026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.