Flight number record

AA 12

American Airlines · Los Angeles to Boston

Route: LAX → BOS
Departs: 08:30
Flights: 364
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s AA 12, check with American Airlines.

AA 12 lands a B, level with the national rate of 77.6%. Roughly one flight in four arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That is a workable record, not a spotless one. That rests on 364 flights, with a median arrival 7 minutes early.

On time

77.2%

Arrivals under 15 minutes late, of 360 completed flights

Avg delay

68 min

Across delayed arrivals only, not all flights

Cancelled

1.10%

National rate is 1.81%

1 hour+ late

8.6%

National rate is 8.1%

These figures cover 364 flights between July 2025 and June 2026. Beyond the headline rate, 8.6% 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.

Schedule

When AA 12 flies

AA 12 flies LAX to BOS without a single fixed slot. Its most common scheduled departure was 08:30, used on 52 of 364 flights, with 08:15 (43 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 08:3052 flights14.3%
Departs 08:1543 flights11.8%

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 08:30 departure sits in the 8am–11am window. Across every US flight scheduled in that window the on-time rate is 84.1%, and AA 12 runs 7 points worse at 77.2%. 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 12 next to LAX to BOS

Every carrier on LAX to BOS combined arrived on time 78.4% of the time across 4,718 flights, so AA 12 is about level with it. American flew 1,146 flights on the same city pair under all its flight numbers, including this one, and those ran 76.5% on time. Across its whole network American Airlines managed 74.4%, which this flight beats by 3 points.

AA 12 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
AA 12thin sample	364	77.2%	68 min	1.10%	B
All American Airlines on LAX–BOS	1,146	76.5%	91 min	1.31%	B
All carriers on LAX–BOS	4,718	78.4%	81 min	1.42%	B
American Airlines, whole network	986,297	74.4%	85 min	2.29%	C

Across the year

AA 12 quarter by quarter

AA 12 did not run the same all year. Its best quarter was Jan–Mar 2026 at 87.4% on time and its weakest Jul–Sep 2025 at 68.5%, a swing of 19 points on roughly 91 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 202592 flights68.5%
Oct–Dec 202592 flights76.1%
Jan–Mar 202690 flights87.4%
Apr–Jun 202690 flights77.5%

Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, AA 12 ranged from 73.1% on Friday to 84.3% on Tuesday. With about 52 flights behind each day, a spread of 11 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why AA 12 runs late

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 5,611 reported delay minutes.

Carrier
41%
National Airspace System
30%
Late-arriving aircraft
28%
Extreme weather
0%

The largest share of delay minutes, 41%, 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 2,299 of the 5,611 delay minutes reported here. The split is drawn from 5,611 delay minutes reported on AA 12.

Cancellations sit at 1.10% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and routes

What a delay on this flight costs

8.6% 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.

At 2,611 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.

Every one of the 364 flights under AA 12 in the data flew LAX to BOS. The number was not reused on any other city pair, which makes this a clean record of one route.

One caution: this is a thin sample. 364 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 12

For a booking, read AA 12 as 77.2% on time with 1.10% cancelled over 364 flights. Those are rates from the past twelve months, not a forecast for any particular day.

Where to go next

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.

Key figures