IAH to DEN flight delays & on-time performance
Nonstop flights from George Bush Intercontinental Airport to Denver International Airport · 861 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at IAH or DEN right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Houston (IAH) to Denver (DEN) arrived on time 82% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 0.4% were cancelled, and 6% arrived an hour or more late.
- United Airlines was the most punctual airline here (82% on time); Frontier Airlines was the least (80%).
- Departures scheduled around 5am did best (97% on time); around 6pm did worst (65%).
- Tuesday was the most reliable day to fly (85% on time) and Saturday the least (80%).
- The largest source of delay minutes was late-arriving aircraft (42%).
Which airline is most on time from IAH to DEN?
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 | 82% | 0.3% | 13 min | 6.3% | 3,899 |
| Frontier Airlines | 80% | 1.0% | 16 min | 6.9% | 816 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 5am97%195 flights
- 6am90%452 flights
- 7am88%334 flights
- 8am92%378 flights
- 9am84%208 flights
- 10am87%377 flights
- 11am84%260 flights
- 12pm87%370 flights
- 2pm78%292 flights
- 3pm72%104 flights
- 4pm70%395 flights
- 6pm65%415 flights
- 8pm74%395 flights
- 9pm83%157 flights
- 10pm84%334 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday81%0.6% cancelled
- Tuesday85%0.5% cancelled
- Wednesday83%0.5% cancelled
- Thursday82%0.1% cancelled
- Friday81%0.4% cancelled
- Saturday80%0.2% cancelled
- Sunday82%0.4% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Late-arriving aircraft42%
- Airline (crew, maintenance, cleaning, fueling)27%
- Air traffic control & airport congestion26%
- Extreme weather5%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Airline (crew, maintenance, cleaning, fueling)50%
- Extreme weather50%
- Air traffic control & airport congestion0%
- Security0%
IAH to DEN: common questions
- How often are IAH to DEN flights on time?
- 82% 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 Houston to Denver cancelled?
- 0.4% of scheduled flights were cancelled (18 of 4,715).
- How long are typical delays?
- Across all flights the average arrival delay was 13 min (early arrivals count as zero). Flights that were late arrived 68 min behind schedule on average, and 6.4% of flights were an hour or more late.
- How long is taxi time at IAH?
- Flights on this route spent 20 min taxiing from the gate to takeoff on average.
Related routes
Return trip: DEN to IAH — 79% on time
More flights from Houston
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: IAH → DEN, nonstop flights by US airlines that report to the DOT. How we calculate this.