Airport month record
BOSAUG
Boston Logan International in August 2026
- Departures
- 13,188
- Month
- August 2026
- National, same month
- 73.1%
- Carriers
- 10
Historical statistics for August 2026, not live status or a forecast for this year’s August. For today’s conditions at BOS, see live FAA status.
BOS in August carries a cancellation problem, not just a delay problem: 3.6% of scheduled flights never operate, against 1.9% nationally. Of the ones that do fly, about seven flights in ten arrive on time, worth a C− overall. The punctuality figure counts only flights that actually departed, so it flatters an operation that cancels this often. That rests on 13,188 flights, of which American Airlines flew 1,541 at 75.9% on time.
American Airlines is the most reliable of the six carriers covered here at 75.9% on time across 1,541 flights.
Key figures
On time
69.8%
Arrivals under 15 minutes late, of 12,651 completed departures
Avg delay
82 min
Across delayed arrivals only, not all flights
Cancelled
3.60%
Nationally in August: 1.86%
Whole year
74.6%
BOS across all twelve months
These figures cover 13,188 departures from Boston Logan International in August 2026. On time means an arrival less than 15 minutes after the scheduled gate time, the DOT's threshold, and the national comparison uses every US departure in the same month rather than the whole year.
Against the year
August next to BOS's other months
Against BOS's own year, August ran 5 points worse than the twelve-month rate of 74.6%, which makes it number eleven of twelve months, best first.
| Month | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| September 2025 | 11,597 | 75.7% | 73 min | 1.35% | B |
| October 2025 | 12,647 | 73.9% | 75 min | 1.51% | C |
| November 2025 | 11,385 | 78.0% | 75 min | 2.76% | B |
| December 2025 | 11,248 | 68.7% | 71 min | 1.69% | C |
| January 2026 | 10,298 | 73.6% | 78 min | 7.50% | C− |
| February 2026 | 10,232 | 74.8% | 73 min | 8.15% | C− |
| March 2026 | 12,299 | 74.1% | 69 min | 2.69% | C |
| April 2026 | 12,626 | 79.3% | 62 min | 0.31% | B+ |
| May 2026 | 12,694 | 79.4% | 60 min | 0.61% | B+ |
| June 2026 | 12,683 | 76.6% | 72 min | 1.77% | B |
| July 2026 | 13,277 | 70.8% | 83 min | 5.92% | C− |
| August 2026 (this page) | 13,188 | 69.8% | 82 min | 3.60% | C− |
Departure window
The best time of day to leave BOS in August
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 41 points, against 15 points between the best and worst carrier.
- 5am–8am2,580 flights89.7%
- 8am–11am2,833 flights79.7%
- 11am–2pm2,034 flights71.4%
- 2pm–5pm2,180 flights59.8%
- 5pm–8pm2,235 flights53.5%
- 8pm–5am1,326 flights48.9%
Scale runs 40% to 95%.
The 8pm–5am window is where this operation falls apart: 48.9% on time, against 89.7% for the 5am–8am 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 8am–11am window is the busiest, with 2,833 flights scheduled in it.
Across the week, Wednesday is the strongest day at 80.7% on time and Sunday the weakest at 56.9%, a spread of 24 points.
Carrier by carrier
Which airlines ran best at BOS in August
The choice of carrier is not cosmetic here. American Airlines arrives on time 75.9% of the time; Southwest Airlines manages 60.8%. Sample sizes sit next to every figure, because a two-point gap across 735 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| JetBlue Airways | 3,376 | 61.4% | 82 min | 5.60% | D− |
| Republic Airways | 3,293 | 75.1% | 78 min | 6.13% | B− |
| Delta Air Lines | 2,403 | 74.0% | 73 min | 1.12% | C |
| American Airlines | 1,541 | 75.9% | 105 min | 1.49% | B |
| United Airlines | 1,236 | 67.4% | 86 min | 0.89% | C+ |
| Southwest Airlines | 735 | 60.8% | 68 min | 1.77% | D |
| Alaska Airlinesthin sample | 264 | 68.3% | 62 min | 1.89% | C |
| Envoy Airthin sample | 202 | 74.4% | 129 min | 1.49% | C |
| Frontier Airlinesthin sample | 84 | 67.1% | 120 min | 2.38% | C |
| Allegiant Airthin sample | 54 | 79.6% | 79 min | 0.00% | B+ |
Republic Airways cancels 6.1% of what it schedules here, the highest in the table. A cancelled flight never appears in an on-time rate, so read that column alongside the punctuality one rather than after it.
Route by route
Busiest routes out of BOS in August
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| BOS to ORD · Chicago | 793 | 63.1% | 94 min | 1.64% | D |
| BOS to DCA · Washington | 754 | 69.9% | 86 min | 5.57% | C− |
| BOS to LGA · New York | 668 | 74.0% | 94 min | 9.28% | C− |
| BOS to SFO · San Francisco | 513 | 60.7% | 63 min | 1.17% | D |
| BOS to ATL · Atlanta | 480 | 69.9% | 79 min | 2.29% | C |
| BOS to LAX · Los Angeles | 469 | 71.1% | 74 min | 1.28% | C |
| BOS to PHL · Philadelphia | 464 | 74.5% | 109 min | 6.25% | C− |
| BOS to JFK · New York | 442 | 67.4% | 86 min | 11.09% | C− |
| BOS to DEN · Denver | 376 | 65.1% | 78 min | 0.80% | C+ |
| BOS to CLT · Charlottethin sample | 343 | 76.9% | 85 min | 1.17% | B |
| BOS to BWI · Baltimorethin sample | 341 | 74.6% | 67 min | 4.11% | C− |
| BOS to MCO · Orlandothin sample | 338 | 62.7% | 85 min | 3.55% | D− |
| BOS to DFW · Dallas-Fort Worththin sample | 331 | 80.2% | 133 min | 0.30% | B+ |
| BOS to EWR · Newarkthin sample | 324 | 66.9% | 103 min | 6.79% | C− |
| BOS to SEA · Seattlethin sample | 322 | 62.9% | 63 min | 1.86% | D |
| BOS to BNA · Nashvillethin sample | 271 | 66.5% | 77 min | 5.17% | C− |
| BOS to MIA · Miamithin sample | 271 | 78.8% | 94 min | 0.37% | B+ |
| BOS to RDU · Raleighthin sample | 250 | 74.1% | 92 min | 4.00% | C− |
| BOS to DTW · Detroitthin sample | 242 | 66.2% | 89 min | 4.55% | C− |
| BOS to PIT · Pittsburghthin sample | 224 | 64.9% | 74 min | 9.38% | D− |
| BOS to TPA · Tampathin sample | 217 | 70.0% | 76 min | 4.61% | C− |
| BOS to SAN · San Diegothin sample | 207 | 67.8% | 64 min | 1.93% | C |
| BOS to CVG · Cincinnatithin sample | 200 | 70.8% | 78 min | 1.50% | C |
| BOS to IAH · Houstonthin sample | 194 | 73.3% | 86 min | 1.03% | C |
| BOS to FLL · Fort Lauderdalethin sample | 187 | 72.9% | 70 min | 2.67% | C |
Delay causes
What held BOS up in August
Late-arriving aircraft accounts for 44% of the 312,000 delay minutes carriers reported here, and the remaining four split what is left.
- 44%Late-arriving aircraft
- 29%National Airspace System
- 26%Carrier
- 2%Extreme weather
- 0%Security
44% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 312,000 reported delay minutes here, that single category outweighs weather by 28 to one. The split is drawn from 312,065 reported delay minutes.
Cancellations run at 3.60%, against 1.86% nationally. That is about 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.
14.2% of arrivals land a full hour or more behind schedule, against 10.9% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
What to do with this
Flying from BOS in August
For a August trip through BOS: plan on this being one of the airport's harder months. The 5am–8am departures held up best at 89.7% on time, and with 14.2% of arrivals an hour or more late, a connection here deserves more slack than the same trip in May would.
Related
Where to go next
- Boston Logan International (BOS), the whole year
- BOS in September75.7%
- BOS in October73.9%
- BOS in November78.0%
- BOS in December68.7%
- BOS in January73.6%
- BOS in February74.8%
- BOS in March74.1%
- BOS in April79.3%
- BOS in May79.4%
- BOS in June76.6%
- BOS in July70.8%
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.