Carrier route record
F9FLL→SJU
Frontier Airlines · Fort Lauderdale to San Juan
- Flights
- 128
- Period
- July 2025 to June 2026
- Share of route
- 5%
- Carriers
- 4
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Frontier Airlines.
Frontier on FLL to SJU draws a D−. About one flight in three arrives at least 15 minutes late, and the typical late arrival is close to two hours behind schedule. Build slack into anything you connect to. That rests on 128 flights, with a median arrival 8 minutes late.
The national on-time rate over the same period is 77.6%, so Frontier on FLL to SJU runs 13 points behind the country as a whole. Across a thousand flights that is about 134 extra late arrivals.
Key figures
On time
64.2%
Arrivals under 15 minutes late, of 123 completed flights
Avg delay
110 min
Across delayed arrivals only, not all flights
Cancelled
3.91%
National rate is 1.81%
Whole route
68.0%
Every carrier on FLL to SJU, 2,344 flights
These figures cover 128 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 FLL to SJU
Frontier flew 128 of the 2,344 flights on FLL to SJU, about 5% of it. Its 64.2% on time is 4 points worse than the route as a whole, which runs 68.0%. Ranked by on-time rate it is number three of four carriers on the route, where the range runs from JetBlue at 71.0% to Spirit at 55.4%. 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 |
|---|---|---|---|---|---|
| JetBlue Airways | 1,646 | 71.0% | 58 min | 1.22% | C |
| Southwest Airlinesthin sample | 279 | 64.7% | 48 min | 0.36% | D+ |
| Frontier Airlines (this page)thin sample | 128 | 64.2% | 110 min | 3.91% | D− |
| Spirit Airlinesthin sample | 291 | 55.4% | 68 min | 1.72% | D |
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 14 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am—
- 8am–11am32 flights76.7%
- 11am–2pm54 flights62.3%
- 2pm–5pm8 flights—
- 5pm–8pm6 flights—
- 8pm–5am28 flights—
Scale runs 55% to 80%. Rows with fewer than 30 flights show a dash.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 62.3% on time against 76.7% for 8am–11am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 11am–2pm window is the busiest, with 54 flights scheduled in it.
Across the year
Frontier on FLL to SJU through the year
- Jul–Sep 202518 flights—
- Oct–Dec 202525 flights—
- Jan–Mar 202620 flights—
- Apr–Jun 202665 flights64.6%
Scale runs 55% to 70%. 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 64.2% on time across 128 flights.
Split by quarter, Frontier on FLL to SJU logged 18 flights in Jul–Sep 2025, 25 flights in Oct–Dec 2025, 20 flights in Jan–Mar 2026 and 65 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 64.2% 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 68% of the 4,859 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.
- 68%Late-arriving aircraft
- 26%Carrier
- 5%National Airspace System
- 0%Extreme weather
68% 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 4,859 reported delay minutes here, that single category outweighs weather by 68 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 4,859 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 76.7% on time here.
Cancellations run at 3.91%, against 1.81% nationally. That is about one flight in 25 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
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 1,046 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 81.6% on time across 128 flights, 17 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 17 points of difference.
One caution: this is a thin sample. 128 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 FLL to SJU
Put together: the delay figures matter less here than the 3.91% cancellation rate. A late arrival costs you close to two hours; a cancelled flight costs you the day. Book the 8am–11am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 123 completed flights over 12 months sit behind that.
Related
Where to go next
- FLL to SJU, every carrier
- Frontier on SJU to FLL, the return leg
- JetBlue Airways on FLL to SJU71.0%
- Southwest Airlines on FLL to SJU64.7%
- Spirit Airlines on FLL to SJU55.4%
- Frontier Airlines network-wide record
- Fort Lauderdale-Hollywood International (FLL) delay statistics
- Luis Munoz Marin International (SJU) 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.