Carrier route record
F9IAH→DTW
Frontier Airlines · Houston to Detroit
- Flights
- 121
- Period
- July 2025 to June 2026
- Share of route
- 6%
- Carriers
- 5
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Frontier Airlines.
Frontier on IAH to DTW sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 9 points worse than the national rate of 77.6%. The late ones land roughly 55 minutes behind schedule. That rests on 121 flights. The strongest carrier on the route with a full sample, Delta Air Lines, flew 1,322 at 82.3% on time.
The national on-time rate over the same period is 77.6%, so Frontier on IAH to DTW runs 9 points behind the country as a whole. Across a thousand flights that is about 90 extra late arrivals.
Key figures
On time
68.6%
Arrivals under 15 minutes late, of 118 completed flights
Avg delay
54 min
Across delayed arrivals only, not all flights
Cancelled
1.65%
National rate is 1.81%
Whole route
78.8%
Every carrier on IAH to DTW, 2,137 flights
These figures cover 121 flights between July 2025 and June 2026. Beyond the headline rate, 8.5% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.
Carrier by carrier
Frontier against every carrier on IAH to DTW
Frontier flew 121 of the 2,137 flights on IAH to DTW, about 6% of it. Its 68.6% on time is 10 points worse than the route as a whole, which runs 78.8%. Ranked by on-time rate it is last of five carriers on the route, where the range runs from SkyWest at 100.0% to Frontier at 68.6%. Two of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The two carriers here are closely matched: 6 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 |
|---|---|---|---|---|---|
| SkyWest Airlinesthin sample | 3 | 100.0% | — | 0.00% | A+ |
| Delta Air Lines | 1,322 | 82.3% | 76 min | 0.76% | B+ |
| Spirit Airlines | 408 | 76.4% | 88 min | 2.45% | B |
| United Airlinesthin sample | 283 | 70.3% | 58 min | 1.41% | C |
| Frontier Airlines (this page)thin sample | 121 | 68.6% | 54 min | 1.65% | C |
No carrier stands out. Delta tops the table at 82.3%, 6 points clear of the bottom, which is inside the range this kind of sample moves year to year.
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 26 points, against 6 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am31 flights87.1%
- 8am–11am6 flights—
- 11am–2pm5 flights—
- 2pm–5pm72 flights60.9%
- 5pm–8pm4 flights—
- 8pm–5am3 flights—
Scale runs 50% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 87.1% of the time, against 60.9% for the afternoon window. That is 26 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 72 flights scheduled in it.
Across the year
Frontier on IAH to DTW through the year
- Oct–Dec 202517 flights—
- Jan–Mar 202637 flights62.9%
- Apr–Jun 202667 flights68.2%
Scale runs 55% to 75%. 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 68.6% on time across 121 flights.
Split by quarter, Frontier on IAH to DTW logged 17 flights in Oct–Dec 2025, 37 flights in Jan–Mar 2026 and 67 flights in Apr–Jun 2026. Fewer than three of those quarters carried the 30 completed flights this site needs before printing a rate, so the 68.6% annual figure is the one to use.
Delay causes
Why Frontier runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 48% of the 1,981 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.
- 48%Late-arriving aircraft
- 26%National Airspace System
- 26%Carrier
48% 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 1,981 reported delay minutes here, that single category outweighs weather by 48 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 1,981 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 87.1% on time here.
Cancellations sit at 1.65% against a national 1.81%, which is ordinary. Diversions add another 0.83%.
Connections and stage length
What a delay here costs
8.5% 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 roughly 55 minutes, which a normal layover absorbs.
The 1,075 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. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg is a different operation and performs like one: it runs 65.5% on time across 120 flights, 3 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 3 points of difference.
One caution: this is a thin sample. 121 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 IAH to DTW
Put together: treat all of this as provisional. 121 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 68.6% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 118 completed flights over 12 months sit behind that.
Related
Where to go next
- IAH to DTW, every carrier
- Frontier on DTW to IAH, the return leg
- Delta Air Lines on IAH to DTW82.3%
- Spirit Airlines on IAH to DTW76.4%
- United Airlines on IAH to DTW70.3%
- Frontier Airlines network-wide record
- George Bush Intercontinental (IAH) delay statistics
- Detroit Metropolitan Wayne County (DTW) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
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.