Route profile
RDU→IAH
Flight reliability, delays and best times to fly from Raleigh–Durham to Houston, 1,042 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 51% of comparable major US routes (4,598 compared)
Calculated from 2,712 flights. How this is calculated · What counts as on time
RDU → IAH arrives on time 81.0% of the time; the return trip, IAH → RDU, arrives on time 78.4% of the time, a 2.6-point gap between the two directions of the same city pair.
RDU → IAH spends 30.7 minutes on the ground on a 1,042-mile trip: 17.5 minutes from pushback to wheels-up at RDU and 13.2 minutes from touchdown to gate at IAH.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
On-time performance swings unusually widely by time of day here, wider than 98% of 4,023 comparable routes.
90.0% on time for 5–9 AM departures, against 53.8% for 6–9 PM.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 4,023 in the comparison.
What sets this route apart
Where RDU to IAH differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
RDU to IAH is at its best against routes of similar length for flights scheduled at 4 PM: 79.3% arrive on time, 11.9 points ahead of the 67.4% those routes manage at that hour. Against all other routes the gap is 8.6 points.
RDU to IAH holds up on Sundays better than routes of similar length do: 81.0% on time to their 73.1%, a 7.9 points lead. Against all other routes the gap is 6.2 points.
March is kinder to RDU to IAH than to routes of similar length: 86.7% on time against 75.2%, 11.5 points better. Against all other routes the gap is 8.8 points.
United Airlines does better on RDU to IAH than on its routes of similar length: 84.6% on time here, 80.5% there, 4.1 points apart. Against all other routes the gap is 4.7 points.
RDU to IAH against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 4 PM departures | 79.3% | routes of similar length | 67.4% | +11.9 pts | 589 here, 152,887 there |
| Weekday: Sunday | 81.0% | routes of similar length | 73.1% | +7.9 pts | 400 here, 424,087 there |
| Month: March | 86.7% | routes of similar length | 75.2% | +11.5 pts | 211 here, 254,489 there |
| Airline: United Airlines | 84.6% | routes of similar length | 80.5% | +4.1 pts | 2,150 here, 406,301 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 1,042 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
When it goes wrong
July 2023 – July 2026
41 min late
against a median of 6 min early
Percentiles over 2,712 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at IAH after arriving from RDU.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 36% | Likely to miss |
| 45 min | 18% | High risk |
| 60 min | 12% | Some risk |
| 90 min | 7.0% | Some risk |
| 120 min | 4.9% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 1.18% of the time and diverts 0.29% of the time, which a late arrival never shows up in.
Chance of missing is the share of 2,672 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 41 minutes late (90th-percentile gate arrival delay), over 2,712 operations.
Any other layover length: connection checker.
Best time to fly
RDU → IAH flights departing 5–9 AM arrived on time 90.0% of the time, against 53.8% for 6–9 PM departures, a gap of 36.2 percentage points.
By departure window
By departure hour
- 12 AM to 5 AM: too few flights to score
- 6 AM: 91.3% on time from 1,065 flights
- 7 AM to 9 AM: too few flights to score
- 10 AM: 80.0% on time from 141 flights
- 11 AM to 3 PM: too few flights to score
- 4 PM: 79.3% on time from 595 flights
- 5 PM: 67.5% on time from 462 flights
- 6 PM to 11 PM: too few flights to score
Why RDU → IAH runs late
July 2023 – July 2026
the inbound aircraft was late, so this flight started late
crew, maintenance, boarding and fueling, all within the carrier’s control
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
Share of the delay minutes US DOT attributed to each cause for RDU → IAH. Only delays of 15 minutes or more are attributed. What the five causes mean
Late-arriving aircraft is the largest cause on RDU → IAH, at 40.4%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 90.0% of the time and 6–9 PM departures 53.8%.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| United Airlines | 2,180 | 84.6% | 1.06% | -8 min | 6.1% |
| Frontier Airlines | 473 | 64.4% | 1.90% | 2 min | 12.7% |
United Airlines flew 82.2% of the 2,653 flights listed.
United Airlines arrived on time 20.2 percentage points more often than Frontier Airlines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| UA2407 United Airlines | 5:00 PM | 708 | 77.1% |
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Monday the least, a gap of 8.1 percentage points.
By month
- Jan: 84.1%
- Feb: 88.5%
- Mar: 86.7%
- Apr: 87.6%
- May: 75.3%
- Jun: 72.7%
- Jul: 71.7%
- Aug: 79.1%
- Sep: 83.6%
- Oct: 85.4%
- Nov: 81.2%
- Dec: 81.6%
July is historically the weakest month and February the strongest, a spread of 16.8 percentage points.
Reliability over time
July 2023 – July 2026
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 85.3% against 77.5% in the 12 months before — improving by 7.8 percentage points.
Data and methodology
Calculated by FlyerIntel from 2,712 RDU → IAH flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed