Flight number record
AA 1259
American Airlines · Boston to Miami
- Route
- BOS → MIA
- Departs
- 08:00
- Flights
- 312
- Period
- July 2025 to June 2026
Historical statistics for July 2025 to June 2026, not live status. For today’s AA 1259, check with American Airlines.
AA 1259 earns an A. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 10 points better than the national rate of 77.6%. When something does go wrong the average delay runs a little over an hour. That rests on 312 flights, with a median arrival 16 minutes early.
Set against the rest of the country, AA 1259's record is 10 points better than the US average of 77.6%. That gap is worth roughly 103 fewer late arrivals for every thousand flights.
Key figures
On time
87.9%
Arrivals under 15 minutes late, of 305 completed flights
Avg delay
75 min
Across delayed arrivals only, not all flights
Cancelled
2.24%
National rate is 1.81%
1 hour+ late
5.2%
National rate is 8.1%
These figures cover 312 flights between July 2025 and June 2026. The median arrival is 16 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
Schedule
When AA 1259 flies
AA 1259 flies BOS to MIA without a single fixed slot. Its most common scheduled departure was 08:00, used on 122 of 312 flights, with 07:00 (72 flights) and 07:20 (32 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.
- Departs 08:00122 flights39.1%
- Departs 07:0072 flights23.1%
- Departs 07:2032 flights10.3%
Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.
Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.
A 08:00 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and AA 1259 runs 4 points better at 87.9%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.
Against the route
AA 1259 next to BOS to MIA
Every carrier on BOS to MIA combined arrived on time 77.7% of the time across 3,417 flights, so AA 1259 is 10 points ahead of it. American flew 2,231 flights on the same city pair under all its flight numbers, including this one, and those ran 82.3% on time. Across its whole network American Airlines managed 74.4%, which this flight beats by 14 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| AA 1259thin sample | 312 | 87.9% | 75 min | 2.24% | A |
| All American Airlines on BOS–MIA | 2,231 | 82.3% | 74 min | 1.75% | B |
| All carriers on BOS–MIA | 3,417 | 77.7% | 75 min | 2.25% | B |
| American Airlines, whole network | 986,297 | 74.4% | 85 min | 2.29% | C |
Across the year
AA 1259 quarter by quarter
AA 1259 did not run the same all year. Its best quarter was Apr–Jun 2026 at 93.6% on time and its weakest Oct–Dec 2025 at 83.5%, a swing of 10 points on roughly 78 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.
- Jul–Sep 202588 flights89.5%
- Oct–Dec 202592 flights83.5%
- Jan–Mar 202685 flights87.7%
- Apr–Jun 202647 flights93.6%
Scale runs 75% to 100%. Rows with fewer than 30 flights show a dash.
By weekday, AA 1259 did best on Wednesday at 97.7% on time and worst on Sunday at 75.6%. Each day rests on about 45 flights, so a gap of 22 points is worth noticing but could still narrow in another year.
Delay causes
Why AA 1259 runs late
One category carries most of the weight here. Carrier accounts for 54% of the 2,791 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%Carrier
- 32%National Airspace System
- 12%Late-arriving aircraft
- 2%Extreme weather
The largest share of delay minutes, 54%, 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 1,519 of the 2,791 delay minutes reported here. The split is drawn from 2,791 delay minutes reported on AA 1259.
Cancellations sit at 2.24% against a national 1.81%, which is ordinary. Diversions add another 0.00%.
Connections and routes
What a delay on this flight costs
5.2% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last a little over an hour, which a normal layover absorbs.
The 1,258 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 same number turns up on one other city pair in the data, including DTW to ORD (43), but none flew often enough under AA 1259 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to BOS to MIA only.
One caution: this is a thin sample. 312 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 AA 1259
For a booking, read AA 1259 as 87.9% on time with 2.24% cancelled over 312 flights. Those are rates from the past twelve months, not a forecast for any particular day.
Related
Where to go next
- BOS to MIA, every carrier and departure
- MIA to BOS, the return direction
- Delta Air Lines 776 on the same route61.6%
- Delta Air Lines 1399 on the same route84.9%
- American Airlines 2980 on the same route93.9%
- Boston Logan International (BOS) delay statistics
- Miami International (MIA) delay statistics
- American Airlines on-time record
- Every American Airlines flight number with a record
- The most and least reliable flight numbers in the US
- Worst months to fly in the US, ranked by the data
A flight number here means American Airlines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.
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.