66% of flights from Baltimore to San Juan arrived on time over the past 12 months. That is worse than the typical U.S. route. The 6 a.m. departures ran on time 76% of the time; the 8 p.m. ones 56%. Most reliable airline: Spirit Airlines (73%). 12% of flights arrived more than an hour late or not at all.
How late?
The on-time rate treats a flight 20 minutes late the same as one 5 hours late. Here's the split for BWI → SJU: when a flight was late, it was under 45 minutes late 59% of the time. About 1 in 11 flights landed an hour or more late, and 1 in 58 three hours or more; 2.5% were cancelled outright.
- On time or early66%
- 15–30 min late12%
- 30–60 min late10%
- 1–2 hours late5.8%
- 2–3 hours late1.7%
- 3+ hours late1.7%
- Diverted0.0%
- Cancelled2.5%
Share of all 1,150 scheduled flights, past 12 months, by arrival time against schedule.
By airline
| Airline | Flights | On time | Cancelled | Typical arrival | 1h+ late | Avg when late | Operated by |
|---|---|---|---|---|---|---|---|
| Southwest Airlines | 812 | 67% | 0.9% | +5 min | 8.0% | +54 min | Southwest Airlines |
| Frontier Airlines | 184 | 59% | 6.5% | +6 min | 16.8% | +106 min | Frontier Airlines |
| Spirit Airlines | 154 | 73% | 6.5% | −3 min | 7.1% | +75 min | Spirit Airlines |
Airline = the name on the ticket. Regional flights (e.g. "Delta Connection") count under the ticketing airline, and the operator is listed.
Best time of day to fly
On-time rate by scheduled departure hour (local time at BWI). Delays build through the day as late planes knock on, so early flights usually do best.
By airline and hour
| Departs | Southwest Airlines | Spirit Airlines |
|---|---|---|
| 6 a.m. | — | 74% |
| 8 a.m. | 75% | — |
| 6 p.m. | 65% | — |
| 8 p.m. | 50% | — |
Last flight of the day
On BWI → SJU, each airline's last flight of the day was cancelled 1.4% of the time, against 1.5% for its earlier flights, about the same. It arrived 3+ hours late 1.9% of the time (earlier flights: 1.3%). It matters more than the numbers suggest. Miss an earlier flight and there's another one that evening; miss the last one and you're usually waiting until morning.
| Airline | Last departure | Last: cancelled | Last: 3h+ late | Earlier: cancelled | Next morning |
|---|---|---|---|---|---|
| Southwest Airlines | 7:35 p.m. | 0.9% | 1.7% | 0.9% | first flight 8:25 a.m. |
Last flight = the airline's last scheduled departure on this route that day, on days it flies the route at least twice; past 12 months. Times are typical scheduled times over the latest three months.
By month
Each calendar month pooled over 2023–2026. Best: November (77%). Worst: July (54%).
By day of week
| Day | Flights | On time | Cancelled |
|---|---|---|---|
| Monday | 170 | 64% | 4.1% |
| Tuesday | 145 | 72% | 1.4% |
| Wednesday | 142 | 76% | 1.4% |
| Thursday | 169 | 64% | 0.6% |
| Friday | 165 | 66% | 0.6% |
| Saturday | 187 | 67% | 5.3% |
| Sunday | 172 | 56% | 3.5% |
Why flights were late
Share of delay minutes on flights 15+ minutes late, as reported to BTS by the airlines.
Cancellations: weather 16 · airline 9 · air traffic/airport 4
Month by month
Flight numbers on this route
Regular flights with at least 120 scheduled trips in the past year. Sorted by departure time.
| Flight | Departs | Flights | On time | Cancelled | Typical arrival | Operated by |
|---|---|---|---|---|---|---|
| F9 2266 | 8:44 p.m. | 126 | 56% | 6.3% | +10 min | Frontier Airlines |
Worst days in the past year
| Date | Flights | On time | Cancelled |
|---|---|---|---|
| Jan 3, 2026 | 6 | 0% | 6 |
| Jan 5, 2026 | 5 | 0% | 1 |
| Jul 6, 2026 | 4 | 0% | 1 |
| Jul 21, 2026 | 4 | 0% | 0 |
| Dec 14, 2025 | 3 | 0% | 0 |
Nearby airport alternatives
Other ways to make the same trip, using airports within 60 miles of Baltimore or San Juan. IAD → SJU has been 9 points more reliable.
| Route | Flights | On time | Cancelled |
|---|---|---|---|
| BWI → SJU (this route) | 1,150 | 66% | 2.5% |
| IAD → SJU Washington Dulles to San Juan | 698 | 75% | 0.6% |
Questions
How often are flights from BWI to SJU on time?
66% of 1,150 scheduled flights from Baltimore, MD to San Juan, PR arrived within 15 minutes of schedule between September 2025 and August 2026. 2.5% were cancelled.
What is the best time of day to fly BWI to SJU?
Flights scheduled to leave at 6 a.m. were the most reliable (76% on time). The 8 p.m. departures were the least (56%).
Which airline is most on time from BWI to SJU?
Spirit Airlines: 73% of its 154 flights on the route arrived on time. Southwest Airlines: 67%. Frontier Airlines: 59%.
What month has the most delays from BWI to SJU?
July (54% on time). The best month is November (77%), over 2023–2026.
Is the last flight of the day from BWI to SJU more likely to be cancelled?
Not much. Each airline's last BWI–SJU flight of the day was cancelled 1.4% of the time over the past year, against 1.5% for its earlier flights. If the last flight is cancelled, the next one is usually the following morning.
Related
- SJU → BWI (return)
- Baltimore/Washington (BWI) delays by hour
- Flights into San Juan (SJU)
- Southwest Airlines on-time record
- Frontier Airlines on-time record
- Spirit Airlines on-time record
- Connecting off this flight? Check the risk
Domestic flights by the airlines that report to the U.S. DOT, plus their regional partners. "On time" means arriving less than 15 minutes after schedule; cancelled and diverted flights count as not on time. Past performance is a guide, not a forecast. Method.