Route reliability record
BDL→SJU
Hartford to San Juan
- Flights
- 968
- Period
- September 2025 to August 2026
- Distance
- 1,666 mi
- Carriers
- 2
This route draws a D. Roughly one flight in two arrives at least 15 minutes late, and the typical late arrival is an hour and a half behind schedule. Build slack into anything you connect to. That rests on 968 BDL to SJU flights, with a median arrival 7 minutes late.
Best time to fly BDL to SJU: a 8am–11am departure, ideally on a Friday. Flights in that window arrived on time 67.7% of the time and Friday flights 65.7%, against 59.0% for the route overall.
The national on-time rate over the same period is 77.3%, so this route runs 18 points behind the country as a whole. Across a thousand flights that is about 183 extra late arrivals.
Key figures
On time
59.0%
Arrivals under 15 minutes late, of 942 completed flights
Avg delay
91 min
Across delayed arrivals only, not all flights
Cancelled
1.96%
National rate is 1.89%
Best carrier
JetBlue
59.9% on time across 727 flights
These figures cover 968 flights between September 2025 and August 2026. Beyond the headline rate, 16.9% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Carrier by carrier
Which airline is most reliable on BDL to SJU
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 | 727 | 59.9% | 89 min | 1.93% | D |
| Frontier Airlinesthin sample | 241 | 56.3% | 97 min | 2.07% | D |
Flight by flight
Flights on BDL to SJU
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
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Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 16 points, against half a point between the best and worst carrier.
- 5am–8am90 flights67.4%
- 8am–11am258 flights67.7%
- 11am–2pm185 flights53.7%
- 2pm–5pm75 flights64.9%
- 5pm–8pm171 flights51.8%
- 8pm–5am189 flights52.7%
Scale runs 45% to 75%.
The 5pm–8pm window is where this operation falls apart: 51.8% on time, against 67.7% for the 8am–11am 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 8am–11am window is the busiest, with 258 flights scheduled in it.
Explore
Filter BDL to SJU by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On BDL to SJU, the best departure window is 8am–11am at 67.7% on time and the worst is 5pm–8pm at 51.8%, a wide gap of 15.9 points. All US flights leaving 8am–11am ran 83.9%.
- 5–8am67.4%
- 8–11am67.7%
- 11am–2pm53.7%
- 2–5pm64.9%
- 5–8pm51.8%
- 8pm–5am52.7%
best all US flightsScale 45% to 95%.
Across the year
When delays peak on this route
This route's year swings by 35 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
July is the worst month at 38.9% on time, 35 points below May, the best at 73.9%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. December was the busiest month here, with 97 flights.
Across the week, Friday is the strongest day at 65.7% on time and Monday the weakest at 53.6%, a spread of 12 points.
Delay causes
Why this route gets delayed
Late-arriving aircraft accounts for 43% of the 35,000 delay minutes carriers reported here, and the remaining four split what is left.
- 43%Late-arriving aircraft
- 35%Carrier
- 20%National Airspace System
- 2%Extreme weather
43% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 35,000 reported delay minutes here, that single category outweighs weather by 23 to one. The split is drawn from 35,127 reported delay minutes.
The largest share of delay minutes, 35%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 12,000 of the 35,000 delay minutes reported here.
Cancellations sit at 1.96% against a national 1.89%, which is ordinary. Diversions add another 0.72%.
Connections and stage length
What a delay here actually costs
16.9% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
At 1,666 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 69.8% on time across 968 flights, 11 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 11 points of difference.
One caution: this is a thin sample. 968 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.
Work out the risk of missing a connection in SJU after this flight
What to do with this
Booking this route
Put together: treat all of this as provisional. 968 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 59.0% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 942 completed flights over 12 months sit behind that.
Common questions
BDL to SJU questions
How often is BDL to SJU delayed?
Roughly one flight in two arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 41.0% of the 968 flights in this analysis, against 22.7% nationally. Delayed flights are late by an hour and a half on average.
How reliable is BDL to SJU compared with the rest of the country?
59.0% of flights arrive on time here against a national 77.3%, a difference of 18 points against it. That is worth a D on this site's grading scale.
What time of day has the fewest delays on BDL to SJU?
The 8am–11am departure window is the strongest at 67.7% on time. The 5pm–8pm window is the weakest at 51.8%, 16 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are July delays on BDL to SJU?
July is the weakest month at 38.9% on time, compared with 73.9% in May. Across the year that is 35 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- SJU to BDL — the return legseparate record
- Luis Munoz Marin International (SJU) delay statistics
- JetBlue Airways on BDL to SJU59.9%
- Frontier Airlines on BDL to SJU56.3%
- BDL to ORD, a related route75.9%
- MCO to SJU, a related route73.8%
- BDL to ATL, a related route84.2%
- JetBlue Airways on-time record59.9%
- Frontier Airlines on-time record56.3%
- Why the first flight of the morning is statistically safest
- How often a connection fails at the major US hubs
Direction matters. BDL to SJU and SJU to BDL are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
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Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.