Route reliability record
LAX→BOS
Los Angeles to Boston
- Flights
- 4,797
- Period
- September 2025 to August 2026
- Distance
- 2,611 mi
- Carriers
- 4
This route lands a B, about a point worse than the national rate of 77.3%. About one flight in four arrives 15 minutes late or worse, and those flights are late by a little over an hour on average. That rests on 4,797 LAX to BOS flights, of which United Airlines flew 731 at 85.3% on time.
Best time to fly LAX to BOS: a 5am–8am departure, ideally on a Saturday. Flights in that window arrived on time 86.6% of the time and Saturday flights 79.6%, against 76.2% for the route overall.
United Airlines is the most reliable of the four carriers covered here at 85.3% on time across 731 flights.
Key figures
On time
76.2%
Arrivals under 15 minutes late, of 4,705 completed flights
Avg delay
80 min
Across delayed arrivals only, not all flights
Cancelled
1.81%
National rate is 1.89%
Best carrier
United
85.3% on time across 731 flights
These figures cover 4,797 flights between September 2025 and August 2026. Beyond the headline rate, 9.5% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Carrier by carrier
Which airline is most reliable on LAX to BOS
The choice of carrier is not cosmetic here. United Airlines arrives on time 85.3% of the time; JetBlue Airways manages 74.0%. Sample sizes sit next to every figure, because a two-point gap across 1,642 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 731 | 85.3% | 71 min | 0.96% | A+ |
| Delta Air Lines | 1,240 | 75.9% | 89 min | 2.18% | B |
| American Airlines | 1,184 | 74.1% | 94 min | 1.60% | C |
| JetBlue Airways | 1,642 | 74.0% | 67 min | 2.07% | C |
United leads JetBlue by 11 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Flight by flight
Flights on LAX to BOS
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
- Delta 63907:5581.6% · 365 flights
- United 178308:2082.0% · 365 flights
- American 1208:0078.8% · 364 flights
- American 245322:0078.3% · 354 flights
- United 221023:5990.7% · 348 flights
- Delta 43713:0067.5% · 342 flights
- JetBlue 98821:4578.4% · 342 flights
- JetBlue 28808:0066.6% · 330 flights
- Delta 50721:0084.0% · 295 flights
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Best ways to make this trip
The most reliable ways to fly Los Angeles to Boston
Every airline on this route, ranked by how often a scheduled flight actually operated and arrived on time, with its best departure time and most punctual flight number. No nearby airport pair beat these.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. LAX → BOSLos Angeles to Boston | United Airlines | 84.5% | 85.3% | 0.96% | 8pm–5am, Sat | UA 2210 23:59 |
| 2. LAX → BOSLos Angeles to Boston | Delta Air Lines | 74.2% | 75.9% | 2.18% | 8pm–5am, Fri | DL 507 21:00 |
| 3. LAX → BOSLos Angeles to Boston | American Airlines | 72.9% | 74.1% | 1.60% | 5am–8am, Tue | AA 12 08:00 |
| 4. LAX → BOSLos Angeles to Boston | JetBlue Airways | 72.5% | 74.0% | 2.07% | 5am–8am, Fri | B6 988 21:45 |
Success is the share of scheduled flights that operated and arrived less than 15 minutes late, so a cancelled flight counts against it. “(route)” means the best time comes from every carrier on the route rather than this airline alone.
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 19 points, against 11 points between the best and worst carrier.
- 5am–8am618 flights86.6%
- 8am–11am1,436 flights73.2%
- 11am–2pm721 flights68.0%
- 2pm–5pm650 flights69.2%
- 5pm–8pm1 flights—
- 8pm–5am1,371 flights82.3%
Scale runs 60% to 90%. Rows with fewer than 30 flights show a dash.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 68.0% on time against 86.6% for 5am–8am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 8am–11am window is the busiest, with 1,436 flights scheduled in it.
Explore
Filter LAX to BOS by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On LAX to BOS, the best departure window is 5am–8am at 86.6% on time and the worst is 11am–2pm at 68.0%, a wide gap of 18.6 points. All US flights leaving 5am–8am ran 89.3%.
- 5–8am86.6%
- 8–11am73.2%
- 11am–2pm68.0%
- 2–5pm69.2%
- 5–8pm—
- 8pm–5am82.3%
best all US flightsScale 60% to 95%. Cells under 30 flights show a dash.
Across the year
When delays peak on this route
This route's year swings by 13 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.
July is the worst month at 70.2% on time, 13 points below May, the best at 82.8%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. July was the busiest month here, with 483 flights.
Across the week, Saturday is the strongest day at 79.6% on time and Sunday the weakest at 72.8%, a spread of 7 points.
Delay causes
Why this route gets delayed
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 90,000 reported delay minutes.
- 35%Late-arriving aircraft
- 33%Carrier
- 29%National Airspace System
- 3%Extreme weather
- 0%Security
35% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 90,000 reported delay minutes here, that single category outweighs weather by 12 to one. The split is drawn from 89,703 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 86.6% on time here.
Cancellations sit at 1.81% against a national 1.89%, which is ordinary. Diversions add another 0.10%.
Connections and stage length
What a delay here actually costs
9.5% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
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.
The return leg runs 73.7% on time across 4,794 flights, within 3 points 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 4,797 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.
Work out the risk of missing a connection in BOS after this flight
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. May runs 82.8% on time and July 70.2%, a swing of 13 points. If the dates move at all, move them out of July before you think about anything else. 4,705 completed flights over 12 months sit behind that.
Common questions
LAX to BOS questions
How often is LAX to BOS delayed?
About one flight in four arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 23.8% of the 4,797 flights in this analysis, against 22.7% nationally. Delayed flights are late by a little over an hour on average.
Which airline is most reliable on LAX to BOS?
United Airlines leads at 85.3% on time across 731 flights. JetBlue Airways is at the other end on 74.0%, a gap of 11 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 LAX to BOS?
The 5am–8am departure window is the strongest at 86.6% on time. The 11am–2pm window is the weakest at 68.0%, 19 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 July delays on LAX to BOS?
July is the weakest month at 70.2% on time, compared with 82.8% in May. Across the year that is 13 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 LAX — the return legseparate record
- Los Angeles International (LAX) delay statistics
- Boston Logan International (BOS) delay statistics
- United Airlines on LAX to BOS85.3%
- Delta Air Lines on LAX to BOS75.9%
- American Airlines on LAX to BOS74.1%
- JetBlue Airways on LAX to BOS74.0%
- LAX to SFO, a related route60.1%
- DCA to BOS, a related route70.1%
- LAX to JFK, a related route77.5%
- United Airlines on-time record85.3%
- Delta Air Lines on-time record75.9%
- American Airlines on-time record74.1%
- Why the first flight of the morning is statistically safest
- Same route, different airline: where the carrier you pick matters most
Direction matters. LAX to BOS and BOS to LAX are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
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Source: US DOT Bureau of Transportation Statistics, on-time performance data, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.