Carrier route record

F9RDU→IAH

Frontier Airlines · Raleigh to Houston

Flights: 246
Period: September 2025 to August 2026
Share of route: 26%
Carriers: 3

Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Frontier Airlines.

Frontier on RDU to IAH lands a B, level with the national rate of 77.3%. About one flight in four arrives 15 minutes late or worse, and those flights are late by an hour and a half on average. That rests on 246 flights, with a median arrival 7 minutes early.

The US average over the same twelve months is 77.3%, so there is little to separate Frontier on RDU to IAH from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.

On time

76.8%

Arrivals under 15 minutes late, of 241 completed flights

Avg delay

96 min

Across delayed arrivals only, not all flights

Cancelled

2.03%

National rate is 1.89%

Whole route

85.9%

Every carrier on RDU to IAH, 943 flights

These figures cover 246 flights between September 2025 and August 2026. Beyond the headline rate, 8.7% of arrivals land a full hour or more behind schedule, against 8.3% nationally.

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Carrier by carrier

Frontier against every carrier on RDU to IAH

Frontier flew 246 of the 943 flights on RDU to IAH, about 26% of it. Its 76.8% on time is 9 points worse than the route as a whole, which runs 85.9%. Ranked by on-time rate it is last of three carriers on the route, where the range runs from SkyWest at 100.0% to Frontier at 76.8%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.

Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.

On-time performance by carrier on RDU to IAH
Airline	Flights	On time	Avg delay	Cancelled	Grade
SkyWest Airlinesthin sample	1	100.0%	—	0.00%	A+
United Airlines	696	89.1%	80 min	0.86%	A+
Frontier Airlines (this page)thin sample	246	76.8%	96 min	2.03%	B

Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.

Departure window

When Frontier runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 16 points, against half a point between the best and worst carrier.

5am–8am—
8am–11am143 flights83.1%
11am–2pm21 flights—
2pm–5pm—
5pm–8pm57 flights66.7%
8pm–5am25 flights—

Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.

Book the morning departure. Flights leaving between 8am–11am arrive on time 83.1% of the time, against 66.7% for the evening window. That is 16 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 143 flights scheduled in it.

Across the year

Frontier on RDU to IAH through the year

Jul–Sep 202517 flights—
Oct–Dec 202556 flights63.5%
Jan–Mar 202646 flights73.3%
Apr–Jun 202665 flights80.0%
Jul–Sep 202662 flights83.9%

Scale runs 55% to 90%. Rows with fewer than 30 flights show a dash.

Monthly volumes are too low here to break the year into twelve reliable readings. What the twelve-month total says is 76.8% on time across 246 flights.

Frontier on RDU to IAH did not run the same all year. Its best quarter was Jul–Sep 2026 at 83.9% on time and its weakest Oct–Dec 2025 at 63.5%, a swing of 20 points on roughly 62 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Across the week, Thursday is the strongest day at 87.5% on time and Monday the weakest at 67.4%, a spread of 20 points.

Arrival by arrival

How late Frontier on RDU to IAH runs when it is late

Frontier on RDU to IAH often beats the schedule: 92 of 241 completed flights, 38%, arrived 15 minutes or more early. The 56 late arrivals split 17 under half an hour, 18 between 30 and 60 minutes, and 21 an hour or more.

15+ min early92 flights38.2%
Within 15 min93 flights38.6%
15–29 min late17 flights7.1%
30–59 min late18 flights7.5%
1–2 hours late12 flights5.0%
2+ hours late9 flights3.7%

Scale runs 0% to 100%.

Share of 241 completed flights by arrival against schedule.

13 of 53 late departures made up the time and arrived on time, 25% of them. In the other direction, 16 flights left on time yet arrived 15 minutes late or more, so that delay built up after pushback: in the air, in a holding pattern or on the ground at IAH.

The worst days

Worst days for Frontier on RDU to IAH

The latest arrival of the period was on 13 October 2025, 17 hours 54 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. The same cause led on five of the five worst days.

The latest arrivals of Frontier on RDU to IAH in the period
Date	Arrived late by	Largest filed cause
13 October 2025	17 hours 54 minutes	Late-arriving aircraft
20 October 2025	15 hours 18 minutes	Late-arriving aircraft
30 January 2026	4 hours 3 minutes	Late-arriving aircraft
29 May 2026	3 hours 43 minutes	Late-arriving aircraft
23 August 2026	3 hours 2 minutes	Late-arriving aircraft

Delay causes

Why Frontier runs late on this route

Late-arriving aircraft accounts for 74% of the 5,357 delay minutes carriers reported here, and the remaining four split what is left.

Late-arriving aircraft
74%
National Airspace System
15%
Carrier
10%

74% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 5,357 reported delay minutes here, that single category outweighs weather by 74 to one. The split is drawn from 5,357 reported delay minutes.

The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 83.1% on time here.

Cancellations sit at 2.03% against a national 1.89%, which is ordinary. Diversions add another 0.00%.

Connections and stage length

What a delay here costs

8.7% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last an hour and a half, which a normal layover absorbs.

The 1,042 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty.

The return leg runs 79.4% on time across 246 flights, within 3 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.

One caution: this is a thin sample. 246 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.

What to do with this

Booking Frontier on RDU to IAH

Put together: treat all of this as provisional. 246 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 76.8% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 241 completed flights over 12 months sit behind that.

Where to go next

Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated 22 October 2026; recomputed monthly. How this data is collected.

Key figures