78% of flights from Washington to Houston arrived on time over the past 12 months. That is about the typical U.S. route. The noon departures ran on time 89% of the time; the 4 p.m. ones 63%. Most reliable airline: United Airlines (83%). 11% of flights arrived more than an hour late or not at all.
How late?
The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for DCA → IAH: when a flight was late, it was under 45 minutes late 46% of the time. About 1 in 12 flights landed an hour or more late, and 1 in 56 three hours or more; 2.3% were cancelled outright.
- On time or early78%
- 15–30 min late5.6%
- 30–60 min late5.2%
- 1–2 hours late4.7%
- 2–3 hours late1.8%
- 3+ hours late1.8%
- Diverted0.5%
- Cancelled2.3%
Share of all 3,351 scheduled flights, past 12 months, by arrival time against schedule.
By airline
| Airline | Flights | On time | Cancelled | Typical arrival | 1h+ late | Avg when late | Operated by |
|---|---|---|---|---|---|---|---|
| United Airlines | 2,402 | 83% | 0.8% | −15 min | 7.4% | +86 min | United Airlines 99%, Mesa Airlines 1% |
| American Airlines | 949 | 66% | 6.1% | −6 min | 10.4% | +70 min | Republic Airways 54%, PSA Airlines 46% |
Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.
Best time of day to fly
On-time rate by scheduled departure hour (local time at DCA). Delays build through the day as late planes knock on, so early flights usually do best.
By airline and hour
| Departs | United Airlines | American Airlines |
|---|---|---|
| 6 a.m. | 92% | 79% |
| 8 a.m. | 90% | — |
| 11 a.m. | 87% | — |
| noon | 89% | — |
| 1 p.m. | — | 63% |
| 2 p.m. | 78% | — |
| 4 p.m. | 63% | — |
| 7 p.m. | 80% | 55% |
| 8 p.m. | — | 66% |
Last flight of the day
On DCA → IAH, each airline's last flight of the day was cancelled 4.5% of the time, against 1.6% for its earlier flights (2.8× as often). It arrived 3+ hours late 2.7% of the time (earlier flights: 1.5%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.
| Airline | Last departure | Last: cancelled | Last: 3h+ late | Earlier: cancelled | Next morning |
|---|---|---|---|---|---|
| American Airlines | 7:56 p.m. | 8.8% | 2.6% | 4.4% | first flight 7:59 a.m. |
| United Airlines | 7:28 p.m. | 0.8% | 2.7% | 0.8% | first flight 6:00 a.m. |
Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.
If you need to be in IAH tonight, book an earlier flight so there's a backup if it's cancelled.
By month
Each calendar month pooled over 2023–2026. Best: October (88%). Worst: July (66%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 524 | 76% | 3.2% |
| Tuesday | 513 | 79% | 2.5% |
| Wednesday | 511 | 81% | 1.6% |
| Thursday | 505 | 79% | 1.0% |
| Friday | 504 | 76% | 1.6% |
| Saturday | 303 | 84% | 2.0% |
| Sunday | 491 | 74% | 4.1% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: weather 55 · air traffic/airport 15 · airline 7
Month by month
Flight numbers on this route
Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.
| Flight | Departs | Flights | On time | Cancelled | Typical arrival | Operated by |
|---|---|---|---|---|---|---|
| UA 1450 | 6:00 a.m. | 353 | 92% | 1.1% | −18 min | United Airlines |
| UA 697 | 8:20 a.m. | 341 | 89% | 1.2% | −21 min | United Airlines |
| UA 2190 | 10:58 a.m. | 198 | 84% | 0.5% | −14 min | United Airlines |
| UA 382 | 12:40 p.m. | 362 | 89% | 0.3% | −20 min | United Airlines |
| UA 1381 | 2:45 p.m. | 285 | 77% | 0.4% | −7 min | United Airlines |
| UA 1785 | 4:34 p.m. | 321 | 64% | 0.9% | 0 min | United Airlines |
| UA 1678 | 7:59 p.m. | 133 | 70% | 0.8% | −16 min | United Airlines |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| May 1, 2026 | 10 | 0% | 0 |
| Jan 26, 2026 | 10 | 0% | 5 |
| Jan 25, 2026 | 10 | 0% | 10 |
| Mar 16, 2026 | 10 | 0% | 2 |
| Jun 20, 2026 | 5 | 0% | 0 |
Nearby airport alternatives
Other ways to make the same trip, using airports within 60 miles of Washington or Houston. IAD → IAH has been 6 points more reliable.
| Route | Flights | On time | Cancelled |
|---|---|---|---|
| DCA → IAH (this route) | 3,351 | 78% | 2.3% |
| IAD → IAH Washington Dulles to Houston Bush Intercontinental | 1,862 | 84% | 0.5% |
| BWI → IAH Baltimore/Washington to Houston Bush Intercontinental | 1,367 | 77% | 2.2% |
| BWI → HOU Baltimore/Washington to Houston Hobby | 1,471 | 75% | 1.4% |
| DCA → HOU Washington Reagan National to Houston Hobby | 1,053 | 74% | 2.2% |
Questions
How often are flights from DCA to IAH on time?
78% of 3,351 scheduled flights from Washington, DC to Houston, TX arrived within 15 minutes of schedule between September 2025 and August 2026. 2.3% were cancelled.
What is the best time of day to fly DCA to IAH?
Flights scheduled to leave at noon were the most reliable (89% on time). The 4 p.m. departures were the least (63%).
Which airline is most on time from DCA to IAH?
United Airlines: 83% of its 2,402 flights on the route arrived on time. American Airlines: 66%.
What month has the most delays from DCA to IAH?
July (66% on time). The best month is October (88%), over 2023–2026.
Is the last flight of the day from DCA to IAH more likely to be cancelled?
Yes. Each airline's last DCA–IAH flight of the day was cancelled 4.5% of the time over the past year, against 1.6% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- IAH → DCA (return)
- Washington Reagan National (DCA) delays by hour
- Flights into Houston Bush Intercontinental (IAH)
- United Airlines on-time record
- American Airlines on-time record
- Connecting off this flight? Check the risk
Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.