Carrier route record

NKSJU→ATL

Spirit Airlines · San Juan to Atlanta

Flights: 124
Period: July 2025 to June 2026
Share of route: 6%
Carriers: 3

Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Spirit Airlines.

Spirit on SJU to ATL earns an F−, which is as low as this site's scale goes for a reason. Only 37.3% of flights arrive inside the 15-minute window, 40 points worse than the national rate of 77.6%. Late arrivals average about an hour. Treat any tight connection here as a coin flip. That rests on 124 flights. The strongest carrier on the route with a full sample, Delta Air Lines, flew 1,637 at 90.8% on time.

The national on-time rate over the same period is 77.6%, so Spirit on SJU to ATL runs 40 points behind the country as a whole. Across a thousand flights that is about 403 extra late arrivals.

On time

37.3%

Arrivals under 15 minutes late, of 118 completed flights

Avg delay

62 min

Across delayed arrivals only, not all flights

Cancelled

4.84%

National rate is 1.81%

Whole route

82.0%

Every carrier on SJU to ATL, 2,126 flights

These figures cover 124 flights between July 2025 and June 2026. Beyond the headline rate, 19.5% 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

Spirit against every carrier on SJU to ATL

Spirit flew 124 of the 2,126 flights on SJU to ATL, about 6% of it. Its 37.3% on time is 45 points worse than the route as a whole, which runs 82.0%. Ranked by on-time rate it is last of three carriers on the route, where the range runs from Delta at 90.8% to Spirit at 37.3%.

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 90.8% of the time; Frontier Airlines manages 56.9%. Sample sizes sit next to every figure, because a two-point gap across 365 flights means less than a ten-point one.

On-time performance by carrier on SJU to ATL
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines	1,637	90.8%	81 min	0.92%	A+
Frontier Airlines	365	56.9%	92 min	2.19%	D
Spirit Airlines (this page)thin sample	124	37.3%	62 min	4.84%	F−

The spread between Delta and Frontier is 34 points, wide enough that it should decide the booking. On a hundred trips that is 34 more arrivals inside the on-time window.

Departure window

When Spirit runs best on this route

Departure time matters more here than the choice of carrier. The gap between the best and worst window is 33 points, against 34 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am—
8am–11am2 flights—
11am–2pm50 flights23.4%
2pm–5pm55 flights56.4%
5pm–8pm17 flights—
8pm–5am—

Scale runs 15% to 60%. 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 23.4% on time against 56.4% for 2pm–5pm. 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 2pm–5pm window is the busiest, with 55 flights scheduled in it.

Across the year

Spirit on SJU to ATL through the year

Jul–Sep 202549 flights79.6%
Oct–Dec 20252 flights—
Jan–Mar 202649 flights0.0%
Apr–Jun 202624 flights—

Scale runs 0% to 85%. 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 37.3% on time across 124 flights.

Split by quarter, Spirit on SJU to ATL logged 49 flights in Jul–Sep 2025, 2 flights in Oct–Dec 2025, 49 flights in Jan–Mar 2026 and 24 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 37.3% annual figure is the one to use.

Delay causes

Why Spirit runs late on this route

One category carries most of the weight here. National Airspace System accounts for 54% of the 4,620 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.

National Airspace System
54%
Carrier
23%
Late-arriving aircraft
23%
Security
0%

54% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 2,483 minutes out of 4,620, against a national NAS share of 21%. The split is drawn from 4,620 reported delay minutes.

Cancellations run at 4.84%, against 1.81% nationally. That is about one flight in twenty 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. 19.5% 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.

At 1,547 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.

The return leg is a different operation and performs like one: it runs 46.2% on time across 125 flights, 9 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 9 points of difference.

One caution: this is a thin sample. 124 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 Spirit on SJU to ATL

Put together: the delay figures matter less here than the 4.84% cancellation rate. A late arrival costs you about an hour; a cancelled flight costs you the day. Book the 2pm–5pm departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 118 completed flights over 12 months sit behind that.

Where to go next

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.

Key figures