Airport month record
BOSJUL
Boston Logan International in July 2026
- Departures
- 13,277
- Month
- July 2026
- National, same month
- 71.7%
- Carriers
- 10
Historical statistics for July 2026, not live status or a forecast for this year’s July. For today’s conditions at BOS, see live FAA status.
BOS in July carries a cancellation problem, not just a delay problem: 5.9% of scheduled flights never operate, against 2.6% 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 13,277 flights, of which American Airlines flew 1,628 at 76.6% on time.
American Airlines is the most reliable of the six carriers covered here at 76.6% on time across 1,628 flights.
Key figures
On time
70.8%
Arrivals under 15 minutes late, of 12,434 completed departures
Avg delay
83 min
Across delayed arrivals only, not all flights
Cancelled
5.92%
Nationally in July: 2.62%
Whole year
74.6%
BOS across all twelve months
These figures cover 13,277 departures from Boston Logan International in July 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
July next to BOS's other months
Against BOS's own year, July ran 4 points worse than the twelve-month rate of 74.6%, which makes it number ten of twelve months, best first. Cancellations are where July stands out: 5.92% of scheduled departures were called off, 1.9 times the airport's rate across the year. Either side of it, June ran 76.6% on time and August 69.8%, so a trip moved by a few weeks would have landed in a better stretch.
| 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 (this page) | 13,277 | 70.8% | 83 min | 5.92% | C− |
| August 2026 | 13,188 | 69.8% | 82 min | 3.60% | C− |
Departure window
The best time of day to leave BOS in July
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 42 points, against 14 points between the best and worst carrier.
- 5am–8am2,564 flights90.6%
- 8am–11am2,850 flights80.6%
- 11am–2pm2,018 flights73.6%
- 2pm–5pm2,154 flights65.6%
- 5pm–8pm2,299 flights49.8%
- 8pm–5am1,392 flights48.7%
Scale runs 40% to 95%.
The 8pm–5am window is where this operation falls apart: 48.7% on time, against 90.6% 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 2,850 flights scheduled in it.
Across the week, Friday is the strongest day at 76.4% on time and Tuesday the weakest at 61.3%, a spread of 15 points.
Carrier by carrier
Which airlines ran best at BOS in July
The choice of carrier is not cosmetic here. American Airlines arrives on time 76.6% of the time; JetBlue Airways manages 63.0%. Sample sizes sit next to every figure, because a two-point gap across 3,355 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| JetBlue Airways | 3,355 | 63.0% | 85 min | 9.27% | D− |
| Republic Airways | 3,312 | 72.3% | 78 min | 8.42% | C− |
| Delta Air Lines | 2,387 | 74.8% | 75 min | 2.97% | C |
| American Airlines | 1,628 | 76.6% | 103 min | 3.87% | B− |
| United Airlines | 1,203 | 73.8% | 97 min | 2.66% | C |
| Southwest Airlines | 768 | 63.7% | 70 min | 2.86% | D |
| Alaska Airlinesthin sample | 264 | 73.3% | 74 min | 0.76% | C+ |
| Envoy Airthin sample | 205 | 80.5% | 138 min | 1.95% | B |
| Frontier Airlinesthin sample | 81 | 68.8% | 66 min | 1.23% | C |
| Allegiant Airthin sample | 74 | 74.0% | 46 min | 1.35% | C |
JetBlue Airways cancels 9.3% 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 July
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| BOS to ORD · Chicago | 786 | 72.8% | 108 min | 4.58% | C− |
| BOS to DCA · Washington | 760 | 68.1% | 89 min | 9.47% | C− |
| BOS to LGA · New York | 683 | 69.9% | 82 min | 12.01% | C− |
| BOS to SFO · San Francisco | 509 | 63.7% | 70 min | 2.95% | D |
| BOS to LAX · Los Angeles | 484 | 74.4% | 104 min | 3.10% | C− |
| BOS to ATL · Atlanta | 467 | 67.3% | 77 min | 3.21% | C− |
| BOS to PHL · Philadelphia | 441 | 69.0% | 82 min | 7.94% | C− |
| BOS to JFK · New York | 427 | 63.6% | 86 min | 13.82% | D− |
| BOS to DEN · Denver | 396 | 73.0% | 80 min | 2.78% | C |
| BOS to CLT · Charlottethin sample | 361 | 77.1% | 90 min | 4.43% | B− |
| BOS to MCO · Orlandothin sample | 353 | 69.2% | 86 min | 5.95% | C− |
| BOS to DFW · Dallas-Fort Worththin sample | 335 | 81.1% | 86 min | 3.58% | B− |
| BOS to BWI · Baltimorethin sample | 326 | 69.8% | 66 min | 6.13% | C− |
| BOS to SEA · Seattlethin sample | 317 | 70.5% | 62 min | 2.21% | C |
| BOS to EWR · Newarkthin sample | 291 | 66.0% | 96 min | 8.25% | C− |
| BOS to BNA · Nashvillethin sample | 279 | 62.9% | 69 min | 5.38% | D− |
| BOS to MIA · Miamithin sample | 268 | 81.9% | 81 min | 2.61% | B |
| BOS to RDU · Raleighthin sample | 242 | 68.3% | 77 min | 4.96% | C− |
| BOS to DTW · Detroitthin sample | 242 | 62.8% | 83 min | 6.20% | D− |
| BOS to PIT · Pittsburghthin sample | 219 | 66.2% | 88 min | 7.76% | C− |
| BOS to TPA · Tampathin sample | 215 | 66.5% | 63 min | 6.05% | C− |
| BOS to SAN · San Diegothin sample | 212 | 78.0% | 91 min | 3.30% | B− |
| BOS to IAH · Houstonthin sample | 210 | 70.5% | 82 min | 4.76% | C− |
| BOS to CVG · Cincinnatithin sample | 197 | 75.7% | 84 min | 4.06% | B− |
| BOS to FLL · Fort Lauderdalethin sample | 189 | 69.7% | 74 min | 6.88% | C− |
Delay causes
What held BOS up in July
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 302,000 reported delay minutes.
- 42%Late-arriving aircraft
- 30%Carrier
- 26%National Airspace System
- 2%Extreme weather
- 0%Security
42% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 302,000 reported delay minutes here, that single category outweighs weather by 19 to one. The split is drawn from 302,404 reported delay minutes.
Cancellations run at 5.92%, against 2.62% nationally. That is roughly one flight in fifteen 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.
13.4% of arrivals land a full hour or more behind schedule, against 11.3% 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 July
For a July trip through BOS: plan on this being one of the airport's harder months. The 5am–8am departures held up best at 90.6% on time, and with 13.4% 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 August69.8%
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.