Carrier route record
F9PHL→RDU
Frontier Airlines · Philadelphia to Raleigh
- Flights
- 585
- Period
- July 2025 to June 2026
- Share of route
- 23%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Frontier Airlines.
Frontier on PHL to RDU lands a B, 4 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 585 flights. The strongest carrier on the route with a full sample, PSA Airlines, flew 655 at 72.9% on time.
The US average over the same twelve months is 77.6%, so there is little to separate Frontier on PHL to RDU from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
81.2%
Arrivals under 15 minutes late, of 569 completed flights
Avg delay
68 min
Across delayed arrivals only, not all flights
Cancelled
2.56%
National rate is 1.81%
Whole route
75.0%
Every carrier on PHL to RDU, 2,560 flights
These figures cover 585 flights between July 2025 and June 2026. The median arrival is 12 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Carrier by carrier
Frontier against every carrier on PHL to RDU
Frontier flew 585 of the 2,560 flights on PHL to RDU, about 23% of it. Its 81.2% on time is 6 points better than the route as a whole, which runs 75.0%. Ranked by on-time rate it is number two of four carriers on the route, where the range runs from Republic at 83.2% to American at 71.3%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The two carriers here are closely matched: 2 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Republic Airwaysthin sample | 215 | 83.2% | 75 min | 3.26% | B− |
| Frontier Airlines (this page) | 585 | 81.2% | 68 min | 2.56% | B |
| PSA Airlines | 655 | 72.9% | 80 min | 3.51% | C− |
| American Airlines | 1,105 | 71.3% | 81 min | 2.35% | C |
PSA Airlines cancels 3.5% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Flight by flight
Frontier flight numbers on PHL to RDU
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 15 points, against 2 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am198 flights83.1%
- 8am–11am38 flights89.5%
- 11am–2pm202 flights81.5%
- 2pm–5pm61 flights83.1%
- 5pm–8pm68 flights75.0%
- 8pm–5am18 flights—
Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 89.5% of the time, against 75.0% for the evening window. That is 15 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 11am–2pm window is the busiest, with 202 flights scheduled in it.
Across the year
Frontier on PHL to RDU through the year
December is the weak month at 69.2% on time, against 96.4% in May. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. June was the busiest month here, with 60 flights.
Across the week, Wednesday is the strongest day at 89.5% on time and Monday the weakest at 75.0%. 15 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Frontier runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 45% of the 7,314 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.
- 45%Late-arriving aircraft
- 43%Carrier
- 11%National Airspace System
- 0%Extreme weather
45% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 7,314 reported delay minutes here, that single category outweighs weather by 45 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 7,314 reported delay minutes.
The largest share of delay minutes, 43%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 3,177 of the 7,314 delay minutes reported here.
Cancellations run at 2.56%, against 1.81% nationally. That is about one flight in 40 cancelled outright. A cancelled flight is invisible in every on-time figure on this page, so the punctuality numbers above describe only the flights that actually operated.
Connections and stage length
What a delay here costs
6.3% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.
At 337 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 8am–11am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 74.0% on time across 585 flights, 7 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 7 points of difference.
One caution: this is a thin sample. 585 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 PHL to RDU
Put together: treat all of this as provisional. 585 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 81.2% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 569 completed flights over 12 months sit behind that.
Related
Where to go next
- PHL to RDU, every carrier
- Frontier on RDU to PHL, the return leg
- Republic Airways on PHL to RDU83.2%
- PSA Airlines on PHL to RDU72.9%
- American Airlines on PHL to RDU71.3%
- Frontier Airlines network-wide record
- Philadelphia International (PHL) delay statistics
- Raleigh-Durham International (RDU) delay statistics
- The US routes with the most cancellations
- Why the first flight of the morning is statistically safest
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.