Route reliability record
PBI→BOS
West Palm Beach to Boston
- Flights
- 2,181
- Period
- July 2025 to June 2026
- Distance
- 1,197 mi
- Carriers
- 3
This route carries a cancellation problem, not just a delay problem: 3.3% of scheduled flights never operate, against 1.8% nationally. Of the ones that do fly, about two flights in three arrive on time, worth a C− overall. The punctuality figure counts only flights that actually departed, so it flatters an operation that cancels this often. That rests on 2,181 flights, of which Delta Air Lines flew 591 at 67.6% on time.
The national on-time rate over the same period is 77.6%, so this route runs 12 points behind the country as a whole. Across a thousand flights that is about 115 extra late arrivals.
Key figures
On time
66.1%
Arrivals under 15 minutes late, of 2,108 completed flights
Avg delay
81 min
Across delayed arrivals only, not all flights
Cancelled
3.26%
National rate is 1.81%
Best carrier
Delta
67.6% on time across 591 flights
These figures cover 2,181 flights between July 2025 and June 2026. Beyond the headline rate, 15.0% 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
Which airline is most reliable on PBI to BOS
The two carriers here are closely matched: 2 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines | 591 | 67.6% | 89 min | 2.88% | C |
| JetBlue Airways | 1,581 | 65.7% | 78 min | 3.42% | C− |
| American Airlinesthin sample | 9 | 44.4% | 142 min | 0.00% | F+ |
JetBlue Airways cancels 3.4% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
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 46 points, against 2 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am332 flights93.8%
- 8am–11am214 flights81.0%
- 11am–2pm587 flights70.8%
- 2pm–5pm328 flights48.1%
- 5pm–8pm348 flights51.5%
- 8pm–5am372 flights54.8%
Scale runs 40% to 100%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 93.8% of the time, against 48.1% for the afternoon window. That is 46 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 11am–2pm window is the busiest, with 587 flights scheduled in it.
Across the year
When delays peak on this route
This route's year swings by 33 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.
May is the best month on the calendar at 77.3% on time. Shoulder season thins the schedule and takes the summer weather with it, and the operation gets its margin back. March was the busiest month here, with 249 flights.
Across the week, Saturday is the strongest day at 73.8% on time and Sunday the weakest at 58.0%. 16 points is a smaller lever than departure hour, but it is free.
Delay causes
Why this route gets delayed
One category carries most of the weight here. Late-arriving aircraft accounts for 48% of the 58,000 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.
- 48%Late-arriving aircraft
- 26%National Airspace System
- 25%Carrier
- 1%Extreme weather
- 0%Security
48% 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 58,000 reported delay minutes here, that single category outweighs weather by 47 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 58,079 reported delay minutes.
The practical consequence: the 5am–8am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 93.8% on time here.
Cancellations run at 3.26%, against 1.81% nationally. That is about one flight in 30 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 actually costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 15.0% 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.
The 1,197 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.
The return leg runs 65.7% on time across 2,183 flights, within half a point of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.
The sample behind these figures is 2,181 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
What to do with this
Booking this route
Put together: the delay figures matter less here than the 3.26% cancellation rate. A late arrival costs you a little over an hour; 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. 2,108 completed flights over 12 months sit behind that.
Common questions
PBI to BOS questions
How often is PBI to BOS delayed?
About one flight in three arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 33.9% of the 2,181 flights in this analysis, against 22.4% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on PBI to BOS?
Delta Air Lines leads at 67.6% on time across 591 flights. JetBlue Airways is at the other end on 65.7%, a gap of 2 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on PBI to BOS?
The 5am–8am departure window is the strongest at 93.8% on time. The 2pm–5pm window is the weakest at 48.1%, 46 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 September delays on PBI to BOS?
September is the weakest month at 44.6% on time, compared with 77.3% in May. Across the year that is 33 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
- BOS to PBI — the return legseparate record
- Boston Logan International (BOS) delay statistics
- Delta Air Lines on-time record67.6%
- JetBlue Airways on-time record65.7%
- American Airlines on-time record44.4%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
Direction matters. PBI to BOS and BOS to PBI are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.