Carrier route record
F9DEN→GRR
Frontier Airlines · Denver to Grand Rapids
- Flights
- 148
- Period
- September 2025 to August 2026
- Share of route
- 12%
- Carriers
- 4
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Frontier Airlines.
Frontier on DEN to GRR earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 8 points better than the national rate of 77.3%. When something does go wrong the average delay runs a little over an hour. That rests on 148 flights, with a median arrival 10 minutes early.
Set against the rest of the country, Frontier's DEN to GRR record is 8 points better than the US average of 77.3%. That gap is worth roughly 78 fewer late arrivals for every thousand flights.
Key figures
On time
85.1%
Arrivals under 15 minutes late, of 148 completed flights
Avg delay
72 min
Across delayed arrivals only, not all flights
Cancelled
0.00%
National rate is 1.89%
Whole route
76.5%
Every carrier on DEN to GRR, 1,235 flights
These figures cover 148 flights between September 2025 and August 2026. The median arrival is 10 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.
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Carrier by carrier
Frontier against every carrier on DEN to GRR
Frontier flew 148 of the 1,235 flights on DEN to GRR, about 12% of it. Its 85.1% on time is 9 points better than the route as a whole, which runs 76.5%. Ranked by on-time rate it is number two of four carriers on the route, where the range runs from SkyWest at 100.0% to Southwest at 69.5%. Two 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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| SkyWest Airlinesthin sample | 1 | 100.0% | — | 0.00% | A+ |
| Frontier Airlines (this page)thin sample | 148 | 85.1% | 72 min | 0.00% | A+ |
| United Airlines | 727 | 78.3% | 56 min | 0.28% | B+ |
| Southwest Airlinesthin sample | 359 | 69.5% | 43 min | 0.28% | C+ |
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 is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 148 flights.
There are not enough flights in each departure window to split Frontier's DEN to GRR record by time of day without the percentages moving on noise. The headline rate of 85.1% is the reliable figure here.
Across the year
Frontier on DEN to GRR through the year
- Jul–Sep 202521 flights—
- Oct–Dec 202536 flights80.6%
- Jan–Mar 20263 flights—
- Apr–Jun 202643 flights88.4%
- Jul–Sep 202645 flights82.2%
Scale runs 70% to 95%. 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 85.1% on time across 148 flights.
Quarter by quarter Frontier on DEN to GRR held fairly steady: 80.6% in Oct–Dec 2025, 88.4% in Apr–Jun 2026 and 82.2% in Jul–Sep 2026. A spread of 8 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.
Across the week, Friday is the strongest day at 94.3% on time and Monday the weakest at 88.9%, a spread of 5 points.
Arrival by arrival
How late Frontier on DEN to GRR runs when it is late
Frontier on DEN to GRR often beats the schedule: 54 of 148 completed flights, 36%, arrived 15 minutes or more early. The 22 late arrivals split 6 under half an hour, 7 between 30 and 60 minutes, and 9 an hour or more.
- 15+ min early54 flights36.5%
- Within 15 min72 flights48.6%
- 15–29 min late6 flights4.1%
- 30–59 min late7 flights4.7%
- 1–2 hours late6 flights4.1%
- 2+ hours late3 flights2.0%
Scale runs 0% to 100%.
Share of 148 completed flights by arrival against schedule.
7 of 24 late departures made up the time and arrived on time, 29% of them. 5 flights left on time and still arrived late.
The worst days
Worst days for Frontier on DEN to GRR
The latest arrival of the period was on 17 August 2026, 4 hours 21 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. The same cause led on four of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 17 August 2026 | 4 hours 21 minutes | Late-arriving aircraft |
| 12 October 2025 | 4 hours 9 minutes | Late-arriving aircraft |
| 14 September 2025 | 2 hours 47 minutes | Late-arriving aircraft |
| 1 June 2026 | 1 hour 52 minutes | Carrier |
| 15 August 2026 | 1 hour 37 minutes | Late-arriving aircraft |
Delay causes
Why Frontier runs late on this route
Late-arriving aircraft accounts for 55% of the 1,582 delay minutes carriers reported here, and the remaining four split what is left.
- 55%Late-arriving aircraft
- 23%Carrier
- 21%National Airspace System
- 1%Extreme weather
55% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 1,582 reported delay minutes here, that single category outweighs weather by 40 to one. The split is drawn from 1,582 reported delay minutes.
Cancellations are rare at 0.00%, below the national 1.89% and low enough to earn the plus on the grade. Almost no flights are called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
6.1% 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 a little over an hour, which a normal layover absorbs.
The 1,015 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 is a different operation and performs like one: it runs 77.2% on time across 147 flights, 8 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 8 points of difference.
One caution: this is a thin sample. 148 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 DEN to GRR
Put together: treat all of this as provisional. 148 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 85.1% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 148 completed flights over 12 months sit behind that.
Related
Where to go next
- DEN to GRR, every carrier
- Frontier on GRR to DEN, the return leg
- United Airlines on DEN to GRR78.3%
- Southwest Airlines on DEN to GRR69.5%
- Frontier Airlines network-wide record
- Denver International (DEN) delay statistics
- Why the first flight of the morning is statistically safest
- How to read this site: grades, sample sizes, and honest caveats
Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.