Airport month record
BWIAUG
Baltimore/Washington International Thurgood Marshall in August 2025
- Departures
- 8,381
- Month
- August 2025
- National, same month
- 77.4%
- Carriers
- 9
Historical statistics for August 2025, not live status or a forecast for this year’s August. For today’s conditions at BWI, see live FAA status.
BWI in August lands a B+, about a point better than the national rate of 77.4%. About one flight in five arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 8,381 flights, of which Delta Air Lines flew 477 at 85.8% on time.
Delta Air Lines is the most reliable of the four carriers covered here at 85.8% on time across 477 flights.
Key figures
On time
78.8%
Arrivals under 15 minutes late, of 8,292 completed departures
Avg delay
62 min
Across delayed arrivals only, not all flights
Cancelled
0.76%
Nationally in August: 1.08%
Whole year
77.6%
BWI across all twelve months
These figures cover 8,381 departures from Baltimore/Washington International Thurgood Marshall in August 2025. 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 BWI's other months
Against BWI's own year, August ran about a point better than the twelve-month rate of 77.6%, which makes it number seven of twelve months, best first. Cancellations were unusually low for BWI in August, at 0.76% against 1.71% across the year. Either side of it, July ran 66.2% on time and September 85.5%, so a trip moved by a few weeks would have landed in a worse stretch.
| Month | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| July 2025 | 8,922 | 66.2% | 92 min | 3.64% | C− |
| August 2025 (this page) | 8,381 | 78.8% | 62 min | 0.76% | B+ |
| September 2025 | 7,968 | 85.5% | 56 min | 0.18% | A+ |
| October 2025 | 8,475 | 81.4% | 49 min | 0.14% | B+ |
| November 2025 | 7,721 | 82.9% | 62 min | 1.80% | B |
| December 2025 | 7,863 | 70.4% | 54 min | 1.27% | C |
| January 2026 | 6,934 | 82.9% | 53 min | 5.61% | B− |
| February 2026 | 6,552 | 83.1% | 58 min | 3.59% | B− |
| March 2026 | 7,803 | 74.6% | 69 min | 2.58% | C |
| April 2026 | 8,041 | 79.9% | 55 min | 0.34% | B+ |
| May 2026 | 8,161 | 76.7% | 59 min | 0.28% | B+ |
| June 2026 | 8,045 | 70.9% | 63 min | 1.16% | C |
Departure window
The best time of day to leave BWI in August
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 23 points, against 8 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am1,214 flights90.4%
- 8am–11am1,896 flights88.5%
- 11am–2pm1,155 flights82.1%
- 2pm–5pm1,471 flights74.2%
- 5pm–8pm1,566 flights68.0%
- 8pm–5am1,079 flights67.2%
Scale runs 60% to 95%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 90.4% of the time, against 67.2% for the overnight window. That is 23 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 8am–11am window is the busiest, with 1,896 flights scheduled in it.
Across the week, Tuesday is the strongest day at 87.9% on time and Friday the weakest at 74.0%. 14 points is a smaller lever than departure hour, but it is free.
Carrier by carrier
Which airlines ran best at BWI in August
The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 85.8% of the time; Spirit Airlines manages 78.2%. Sample sizes sit next to every figure, because a two-point gap across 470 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Southwest Airlines | 6,204 | 79.1% | 56 min | 0.60% | B+ |
| Delta Air Lines | 477 | 85.8% | 78 min | 0.63% | A+ |
| Spirit Airlines | 470 | 78.2% | 59 min | 1.28% | B |
| United Airlines | 372 | 79.7% | 102 min | 0.54% | B+ |
| American Airlinesthin sample | 288 | 78.6% | 106 min | 2.43% | B |
| Frontier Airlinesthin sample | 287 | 61.7% | 84 min | 1.74% | D |
| Republic Airwaysthin sample | 106 | 85.7% | 63 min | 0.94% | A+ |
| Envoy Airthin sample | 89 | 79.3% | 59 min | 2.25% | B |
| Alaska Airlinesthin sample | 62 | 78.7% | 37 min | 1.61% | B |
Delta leads Spirit by 8 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Route by route
Busiest routes out of BWI in August
| Route | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| BWI to ATL · Atlanta | 493 | 78.9% | 56 min | 1.22% | B |
| BWI to MCO · Orlandothin sample | 362 | 67.0% | 75 min | 0.55% | C+ |
| BWI to BOS · Bostonthin sample | 318 | 79.0% | 67 min | 1.26% | B |
| BWI to DEN · Denverthin sample | 282 | 75.6% | 66 min | 0.35% | B+ |
| BWI to CLT · Charlottethin sample | 271 | 82.5% | 88 min | 1.11% | B |
| BWI to ORD · Chicagothin sample | 252 | 75.5% | 89 min | 1.19% | B |
| BWI to FLL · Fort Lauderdalethin sample | 244 | 81.1% | 54 min | 0.41% | B+ |
| BWI to TPA · Tampathin sample | 230 | 79.5% | 58 min | 0.87% | B+ |
| BWI to DTW · Detroitthin sample | 227 | 84.6% | 97 min | 0.00% | B+ |
| BWI to MIA · Miamithin sample | 197 | 66.3% | 103 min | 0.51% | C+ |
| BWI to MDW · Chicagothin sample | 183 | 74.0% | 82 min | 0.55% | C+ |
| BWI to BNA · Nashvillethin sample | 173 | 82.2% | 51 min | 2.31% | B |
| BWI to PVD · Providencethin sample | 172 | 84.1% | 54 min | 1.16% | B |
| BWI to LAX · Los Angelesthin sample | 169 | 78.6% | 42 min | 0.59% | B+ |
| BWI to DAL · Dallasthin sample | 162 | 76.9% | 57 min | 0.62% | B+ |
| BWI to LAS · Las Vegasthin sample | 160 | 86.2% | 58 min | 0.00% | A+ |
| BWI to BDL · Hartfordthin sample | 150 | 84.4% | 50 min | 2.00% | B |
| BWI to RDU · Raleighthin sample | 149 | 78.9% | 53 min | 1.34% | B |
| BWI to BUF · Buffalothin sample | 148 | 82.3% | 78 min | 0.00% | B+ |
| BWI to ALB · Albanythin sample | 148 | 84.5% | 52 min | 0.00% | B+ |
| BWI to MHT · Manchesterthin sample | 146 | 78.1% | 54 min | 0.00% | B+ |
| BWI to ORF · Norfolkthin sample | 139 | 80.6% | 49 min | 0.00% | B+ |
| BWI to MSP · Minneapolisthin sample | 135 | 85.9% | 37 min | 0.00% | A+ |
| BWI to PWM · Portlandthin sample | 135 | 81.5% | 58 min | 0.00% | B+ |
| BWI to STL · St. Louisthin sample | 129 | 85.0% | 69 min | 1.55% | A |
Delay causes
What held BWI up in August
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 109,000 reported delay minutes.
- 42%Late-arriving aircraft
- 32%Carrier
- 19%National Airspace System
- 6%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. That is a cascade, and cascades start small and grow through the day. Across 109,000 reported delay minutes here, that single category outweighs weather by 7 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 109,217 reported delay minutes.
Cancellations are rare at 0.76%, below the national 1.08% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.
6.8% of arrivals land an hour or more late, close to the national 8.2%. 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 about an hour, which a normal layover absorbs.
What to do with this
Flying from BWI in August
For a August trip through BWI: expect 78.8% on time and 0.76% cancelled, going by August 2025. The 5am–8am window was the strongest part of the day.
Related
Where to go next
- Baltimore/Washington International Thurgood Marshall (BWI), the whole year
- BWI in July66.2%
- BWI in September85.5%
- BWI in October81.4%
- BWI in November82.9%
- BWI in December70.4%
- BWI in January82.9%
- BWI in February83.1%
- BWI in March74.6%
- BWI in April79.9%
- BWI in May76.7%
- BWI in June70.9%
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.