Carrier route record
F9MEM→DEN
Frontier Airlines · Memphis to Denver
- Flights
- 139
- Period
- July 2025 to June 2026
- Share of route
- 10%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Frontier Airlines.
Frontier on MEM to DEN sits in the middle of the pack with a C+. Close to three flights in four arrive on time by the DOT's definition, 3 points worse than the national rate of 77.6%. The late ones land an hour and a half behind schedule. That rests on 139 flights. The strongest carrier on the route with a full sample, United Airlines, flew 728 at 81.2% on time.
The US average over the same twelve months is 77.6%, so there is little to separate Frontier on MEM to DEN from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
74.6%
Arrivals under 15 minutes late, of 138 completed flights
Avg delay
95 min
Across delayed arrivals only, not all flights
Cancelled
0.72%
National rate is 1.81%
Whole route
78.8%
Every carrier on MEM to DEN, 1,333 flights
These figures cover 139 flights between July 2025 and June 2026. Beyond the headline rate, 13.8% 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 MEM to DEN
Frontier flew 139 of the 1,333 flights on MEM to DEN, about 10% of it. Its 74.6% on time is 4 points worse than the route as a whole, which runs 78.8%. Ranked by on-time rate it is last of four carriers on the route, where the range runs from SkyWest at 100.0% to Frontier at 74.6%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
The two carriers here are closely matched: 5 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 | 1 | 100.0% | — | 0.00% | A+ |
| United Airlines | 728 | 81.2% | 79 min | 1.10% | B |
| Southwest Airlines | 465 | 76.3% | 56 min | 0.65% | B+ |
| Frontier Airlines (this page)thin sample | 139 | 74.6% | 95 min | 0.72% | C+ |
No carrier stands out. United tops the table at 81.2%, 5 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 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 139 flights.
There are not enough flights in each departure window to split Frontier's MEM to DEN record by time of day without the percentages moving on noise. The headline rate of 74.6% is the reliable figure here.
Across the year
Frontier on MEM to DEN through the year
- Jul–Sep 202531 flights58.1%
- Oct–Dec 202539 flights82.1%
- Jan–Mar 202637 flights72.2%
- Apr–Jun 202632 flights84.4%
Scale runs 50% 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 74.6% on time across 139 flights.
Frontier on MEM to DEN did not run the same all year. Its best quarter was Apr–Jun 2026 at 84.4% on time and its weakest Jul–Sep 2025 at 58.1%, a swing of 26 points on roughly 35 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, Sunday is the strongest day at 76.2% on time and Thursday the weakest at 62.5%. 14 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Frontier runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 3,308 reported delay minutes.
- 37%Late-arriving aircraft
- 32%Extreme weather
- 23%National Airspace System
- 7%Carrier
Extreme weather accounts for 32% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 5.2 times the usual weather exposure. The split is drawn from 3,308 reported delay minutes.
37% 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 3,308 reported delay minutes here, that single category outweighs weather by 1 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.
Cancellations are rare at 0.72%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
Connections and stage length
What a delay here costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 13.8% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.
The 872 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 82.6% on time across 139 flights, 8 points above 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. 139 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 MEM to DEN
Put together: treat all of this as provisional. 139 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 74.6% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 138 completed flights over 12 months sit behind that.
Related
Where to go next
- MEM to DEN, every carrier
- Frontier on DEN to MEM, the return leg
- United Airlines on MEM to DEN81.2%
- Southwest Airlines on MEM to DEN76.3%
- Frontier Airlines network-wide record
- Denver International (DEN) delay statistics
- Why the first flight of the morning is statistically safest
- How often a connection fails at the major US hubs
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.