Carrier route record
DLPBI→BOS
Delta Air Lines · West Palm Beach to Boston
- Flights
- 591
- Period
- July 2025 to June 2026
- Share of route
- 27%
- Carriers
- 3
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Delta Air Lines.
Delta on PBI to BOS draws a C. About one flight in three 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 591 flights, with a median arrival 2 minutes early.
The national on-time rate over the same period is 77.6%, so Delta on PBI to BOS runs 10 points behind the country as a whole. Across a thousand flights that is about 100 extra late arrivals.
Key figures
On time
67.6%
Arrivals under 15 minutes late, of 574 completed flights
Avg delay
89 min
Across delayed arrivals only, not all flights
Cancelled
2.88%
National rate is 1.81%
Whole route
66.1%
Every carrier on PBI to BOS, 2,181 flights
These figures cover 591 flights between July 2025 and June 2026. Beyond the headline rate, 13.2% 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
Delta against every carrier on PBI to BOS
Delta flew 591 of the 2,181 flights on PBI to BOS, about 27% of it. Its 67.6% on time is 2 points better than the route as a whole, which runs 66.1%. Ranked by on-time rate it is first of three carriers on the route, where the range runs from Delta at 67.6% to American at 44.4%. 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 |
|---|---|---|---|---|---|
| Delta Air Lines (this page) | 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+ |
Departure window
When Delta runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 19 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–8am—
- 8am–11am—
- 11am–2pm274 flights77.2%
- 2pm–5pm8 flights—
- 5pm–8pm94 flights58.7%
- 8pm–5am215 flights60.2%
Scale runs 50% to 85%. Rows with fewer than 30 flights show a dash.
The 5pm–8pm window is where this operation falls apart: 58.7% on time, against 77.2% for the 11am–2pm 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 11am–2pm window is the busiest, with 274 flights scheduled in it.
Across the year
Delta on PBI to BOS through the year
Delays peak in October, when the on-time rate falls to 54.8%. June is the strongest month at 77.8%. Moving a flexible trip across that boundary buys 23 points. April was the busiest month here, with 66 flights.
Across the week, Saturday is the strongest day at 74.4% on time and Sunday the weakest at 61.4%. 13 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Delta runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 54% of the 17,000 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.
- 54%Late-arriving aircraft
- 31%Carrier
- 14%National Airspace System
- 1%Extreme weather
54% 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 17,000 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 16,571 reported delay minutes.
Cancellations run at 2.88%, against 1.81% nationally. That is roughly 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 costs
For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 13.2% 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 is a different operation and performs like one: it runs 70.7% on time across 591 flights, 3 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 3 points of difference.
One caution: this is a thin sample. 591 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 Delta on PBI to BOS
Put together: the delay figures matter less here than the 2.88% cancellation rate. A late arrival costs you an hour and a half; a cancelled flight costs you the day. Book the 11am–2pm departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 574 completed flights over 12 months sit behind that.
Related
Where to go next
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.