Route · BOS → SJU · 2020–2025 BTS data
Boston to San Juan
The BOS–SJU corridor (Boston, MA → San Juan, PR) runs behind the national average, served by 16 carriers across roughly 1,674 miles.
Data updated 2026-06-13
- 69.5%
- On-time
- -9.5 pts
- vs US avg
- 73 min
- Delay when late
- 9,566
- Flights
Cancelled
1.1%
Best Month
Sep 2024 85%
Worst Month
Dec 2024 54%
Distance
1,674 mi
Carriers
16
Monthly Performance
Recent 24 months of route data.
| Period | Flights | Delayed | Cancelled | Diverted | Carriers |
|---|---|---|---|---|---|
| Dec 2025 | 170 | 70 | 1 | 0 | DL,F9,NK,B6 |
| Nov 2025 | 110 | 29 | 1 | 0 | DL,B6 |
| Oct 2025 | 95 | 26 | 1 | 1 | B6,DL |
| Sep 2025 | 83 | 25 | 0 | 0 | DL,B6 |
| Aug 2025 | 181 | 48 | 2 | 1 | NK,B6,DL |
| Jul 2025 | 175 | 34 | 5 | 0 | B6,NK,DL |
| Jun 2025 | 160 | 31 | 0 | 0 | B6,DL,NK |
| May 2025 | 151 | 36 | 0 | 0 | B6,DL,F9,NK |
| Apr 2025 | 193 | 58 | 0 | 2 | DL,F9,NK,B6 |
| Mar 2025 | 212 | 62 | 1 | 2 | B6,NK,DL,F9 |
| Feb 2025 | 187 | 76 | 2 | 2 | B6,DL,F9,NK |
| Jan 2025 | 180 | 61 | 3 | 1 | B6,NK,DL,F9 |
| Dec 2024 | 185 | 86 | 0 | 0 | B6,DL,F9,NK |
| Nov 2024 | 150 | 52 | 1 | 1 | B6,DL,F9 |
| Oct 2024 | 116 | 29 | 1 | 0 | DL,F9,B6 |
| Sep 2024 | 117 | 18 | 1 | 1 | B6,DL,F9 |
| Aug 2024 | 222 | 100 | 6 | 0 | B6,DL,F9,NK |
| Jul 2024 | 230 | 78 | 4 | 0 | B6,DL,F9,NK |
| Jun 2024 | 212 | 67 | 2 | 1 | B6,DL,F9,NK |
| May 2024 | 162 | 41 | 3 | 0 | B6,DL,NK |
| Apr 2024 | 171 | 38 | 3 | 0 | B6,DL,NK |
| Mar 2024 | 163 | 47 | 1 | 0 | B6,DL,NK |
| Feb 2024 | 156 | 60 | 3 | 0 | B6,DL,NK |
| Jan 2024 | 156 | 52 | 1 | 0 | B6,DL,NK |
Cancellation Rate
1.1%
42 of 3,937 flights
Diversion Rate
0.3%
12 of 3,937 flights
Explore origin & destination
On-time and delay data for the airports this route connects.
BOS - Boston
Full on-time, delay-cause, and seasonal performance for Boston, MA.
Origin airport →SJU - San Juan
Full on-time, delay-cause, and seasonal performance for San Juan, PR.
Destination airport →Compare the two airports
See BOS and SJU side by side on delays, cancellations, and reliability.
Open comparison tool →Similar routes
Other BTS-tracked routes with comparable performance or trip length to BOS–SJU.
Routes with a similar on-time rate
What the Data Says About BOS to SJU
On-time performance on the BOS to SJU pairing (Boston to San Juan) trails a chunk of the network: 69.5% of 9,566 tracked flights arrived on schedule, with a 73.3-minute average delay on the ones that ran late. The route spans about 1,674 miles across 16 carriers. Cancellations over the trailing 24 months hit 1.1% (42 of 3,937 flights), with 0.3% diverted.
The monthly split is wide on this route: Sep 2024 posted the strongest performance at 85% on-time, while Dec 2024 came in at just 54% - a 31-point swing worth factoring into travel timing.
Frequently Asked Questions
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Data source
Data Source: Bureau of Transportation Statistics (BTS), On-Time Performance Data. Statistics reflect cumulative performance across all available reporting periods.
Read our methodology - how this data is sourced, computed, and verified.
Every figure on PlainFlights is rendered directly from BTS On-Time Performance data, no number is typed in by an editor. This page aggregates this specific route's on-time performance and monthly trend, live from the dataset. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.