Carrier route record
NKSJU→BWI
Spirit Airlines · San Juan to Baltimore
- Flights
- 205
- Period
- July 2025 to June 2026
- Share of route
- 17%
- 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 BWI 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 close to two hours behind schedule. That rests on 205 flights, with a median arrival 3 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate Spirit on SJU to BWI from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
74.3%
Arrivals under 15 minutes late, of 191 completed flights
Avg delay
106 min
Across delayed arrivals only, not all flights
Cancelled
6.34%
National rate is 1.81%
Whole route
77.9%
Every carrier on SJU to BWI, 1,184 flights
These figures cover 205 flights between July 2025 and June 2026. Beyond the headline rate, 12.6% 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 BWI
Spirit flew 205 of the 1,184 flights on SJU to BWI, about 17% of it. Its 74.3% on time is 4 points worse than the route as a whole, which runs 77.9%. Ranked by on-time rate it is number two of three carriers on the route, where the range runs from Southwest at 80.3% to Frontier at 69.4%. One 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 |
|---|---|---|---|---|---|
| Southwest Airlines | 822 | 80.3% | 48 min | 0.97% | B+ |
| Spirit Airlines (this page)thin sample | 205 | 74.3% | 106 min | 6.34% | C− |
| Frontier Airlinesthin sample | 157 | 69.4% | 53 min | 5.10% | C− |
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 26 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–8am44 flights90.7%
- 8am–11am7 flights—
- 11am–2pm13 flights—
- 2pm–5pm3 flights—
- 5pm–8pm10 flights—
- 8pm–5am128 flights64.7%
Scale runs 55% to 95%. Rows with fewer than 30 flights show a dash.
The 8pm–5am window is where this operation falls apart: 64.7% on time, against 90.7% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 8pm–5am window is the busiest, with 128 flights scheduled in it.
Across the year
Spirit on SJU to BWI through the year
- Jul–Sep 202561 flights82.8%
- Oct–Dec 202534 flights91.2%
- Jan–Mar 202681 flights62.0%
- Apr–Jun 202629 flights—
Scale runs 55% 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 74.3% on time across 205 flights.
Spirit on SJU to BWI did not run the same all year. Its best quarter was Oct–Dec 2025 at 91.2% on time and its weakest Jan–Mar 2026 at 62.0%, a swing of 29 points on roughly 68 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.
Delay causes
Why Spirit runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 42% of the 5,202 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.
- 42%Late-arriving aircraft
- 38%Carrier
- 18%National Airspace System
- 2%Extreme weather
42% 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 5,202 reported delay minutes here, that single category outweighs weather by 28 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 5,202 reported delay minutes.
The largest share of delay minutes, 38%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 1,967 of the 5,202 delay minutes reported here.
Cancellations run at 6.34%, against 1.81% nationally. That is about one flight in fifteen 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. 12.6% 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 1,565 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 runs 71.5% on time across 205 flights, within 3 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
One caution: this is a thin sample. 205 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 BWI
Put together: the delay figures matter less here than the 6.34% cancellation rate. A late arrival costs you close to two hours; a cancelled flight costs you the day. Book the 5am–8am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 191 completed flights over 12 months sit behind that.
Related
Where to go next
- SJU to BWI, every carrier
- Spirit on BWI to SJU, the return leg
- Southwest Airlines on SJU to BWI80.3%
- Frontier Airlines on SJU to BWI69.4%
- Spirit Airlines network-wide record
- Luis Munoz Marin International (SJU) delay statistics
- Baltimore/Washington International Thurgood Marshall (BWI) 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.