Carrier route record
DLBOS→PBI
Delta Air Lines · Boston to West Palm Beach
- 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 BOS to PBI sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 7 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 591 flights, with a median arrival 4 minutes early.
The national on-time rate over the same period is 77.6%, so Delta on BOS to PBI runs 7 points behind the country as a whole. Across a thousand flights that is about 69 extra late arrivals.
Key figures
On time
70.7%
Arrivals under 15 minutes late, of 573 completed flights
Avg delay
74 min
Across delayed arrivals only, not all flights
Cancelled
2.37%
National rate is 1.81%
Whole route
65.7%
Every carrier on BOS to PBI, 2,183 flights
These figures cover 591 flights between July 2025 and June 2026. Beyond the headline rate, 11.5% 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 BOS to PBI
Delta flew 591 of the 2,183 flights on BOS to PBI, about 27% of it. Its 70.7% on time is 5 points better than the route as a whole, which runs 65.7%. Ranked by on-time rate it is first of three carriers on the route, where the range runs from Delta at 70.7% to American at 55.6%. 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 | 70.7% | 74 min | 2.37% | C |
| JetBlue Airways | 1,583 | 64.0% | 71 min | 3.28% | D− |
| American Airlinesthin sample | 9 | 55.6% | 162 min | 0.00% | D+ |
Flight by flight
Delta flight numbers on BOS to PBI
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 27 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–8am112 flights77.9%
- 8am–11am162 flights86.2%
- 11am–2pm16 flights—
- 2pm–5pm301 flights59.7%
- 5pm–8pm—
- 8pm–5am—
Scale runs 50% to 90%. Rows with fewer than 30 flights show a dash.
Book the morning departure. Flights leaving between 8am–11am arrive on time 86.2% of the time, against 59.7% for the afternoon window. That is 27 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 2pm–5pm window is the busiest, with 301 flights scheduled in it.
Across the year
Delta on BOS to PBI through the year
Delays peak in October, when the on-time rate falls to 41.9%. June is the strongest month at 86.1%. Moving a flexible trip across that boundary buys 44 points. April was the busiest month here, with 66 flights.
Across the week, Tuesday is the strongest day at 76.0% on time and Monday the weakest at 66.7%. 9 points is a smaller lever than departure hour, but it is free.
Delay causes
Why Delta runs late on this route
Carriers report a reason for every delay minute they cause, in five DOT categories. The split below is by minutes, not by number of flights, so a handful of very long weather delays weighs as much as many short ones. It covers 12,000 reported delay minutes.
- 40%Carrier
- 29%Late-arriving aircraft
- 29%National Airspace System
- 1%Security
- 0%Extreme weather
The largest share of delay minutes, 40%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 5,022 of the 12,000 delay minutes reported here. The split is drawn from 12,450 reported delay minutes.
The practical consequence: the 8am–11am departure is the one that starts clean. Its aircraft has no earlier leg to be late from, which is exactly why that window shows 86.2% on time here.
Cancellations sit at 2.37% against a national 1.81%, which is ordinary. Diversions add another 0.68%.
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. 11.5% 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 67.6% on time across 591 flights, 3 points below 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 BOS to PBI
Put together: treat all of this as provisional. 591 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 70.7% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 573 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.