Route profile
DEN→IAH
Flight reliability, delays and best times to fly from Denver to Houston. · 862 miles
Right now
Current conditions at both ends of this route.
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Airport conditions describe the airfield, not any individual flight. An airport operating normally is not a guarantee that a specific flight will depart on time.
Route reliability
July 2023 – June 2026
Better than 46% of comparable major US routes (4,577 compared)
Calculated from 14,528 flights. How this is calculated
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – June 2026
Best time to fly
On-time arrival rate by scheduled local departure time.
DEN → IAH flights departing 5–9 AM arrived on time 87.9% of the time, against 71.0% for 3–6 PM departures — a gap of 16.9 percentage points.
By departure window
By departure hour
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026 · Buckets with fewer than 120 flights are not scored.
Airlines on this route
Performance by the carrier that actually operated the flight.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| United Airlines | 11,445 | 77.3% | 0.78% | -4 min | 8.1% |
| Frontier Airlines | 2,001 | 74.8% | 1.05% | -7 min | 9.2% |
| Southwest Airlines | 1,082 | 76.0% | 1.02% | -3 min | 6.9% |
United Airlines arrived on time 2.5 percentage points more often than Frontier Airlines on this route.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026 · Carriers with fewer than 200 flights on this route are not listed.
Other ways to fly Denver to Houston
Airport pairs serving the same journey, grouped by the DOT's own city-market definition. They do not perform the same way.
| Route | Flights | On time | Cancelled | Median delay | Score |
|---|---|---|---|---|---|
| DEN→IAH this route Denver to Houston | 14,528 | 76.9% | 0.83% | -5 min | 65 |
| DEN→HOU Denver to Houston | 7,627 | 74.2% | 0.96% | -3 min | 63 |
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026 · Grouped by DOT city market, which places Newark with the New York airports and Baltimore with the Washington ones.
Individual flights on this route
The same route is not equally reliable at every hour. These are the flight numbers with enough operating history to judge separately.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| UA489 United Airlines | 3:40 PM | 934 | 71.3% |
| UA475 United Airlines | 7:20 PM | 909 | 72.2% |
| UA1720 United Airlines | 7:45 AM | 711 | 89.3% |
| UA1829 United Airlines | 1:25 PM | 620 | 72.2% |
| F93206 Frontier Airlines | 7:00 AM | 590 | 79.6% |
| UA320 United Airlines | 5:00 AM | 574 | 94.4% |
| UA2419 United Airlines | 8:31 PM | 475 | 74.9% |
| F92996 Frontier Airlines | 9:06 PM | 411 | 71.5% |
| F94856 Frontier Airlines | 8:40 PM | 328 | 68.2% |
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026 · Flight numbers with fewer than 270 operations on this route, or no longer scheduled, are not listed.
Weekly and seasonal patterns
By day of week
Wednesday is historically the most reliable day and Friday the least, a gap of 6.1 percentage points.
By month
July is historically the weakest month and October the strongest, a spread of 22.2 percentage points.
Historical trend
On-time arrival rate by month.
Over the most recent 12 months (2025-07 to 2026-06), on-time arrivals averaged 78.2% against 77.4% in the 12 months before — broadly unchanged.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – June 2026
Data and methodology
All figures on this page are calculated by FlyerIntel from 14,528 DEN → IAH flight records published by the US DOT Bureau of Transportation Statistics, covering July 2023 – June 2026. A flight is counted as delayed when it arrives 15 or more minutes after its scheduled arrival time, following BTS methodology. Cancelled and diverted flights have no arrival time and are excluded from on-time rates rather than counted as late.