Carrier route record
YXBWI→BOS
Republic Airways · Baltimore to Boston
- Flights
- 1,099
- Period
- September 2025 to August 2026
- Share of route
- 31%
- Carriers
- 3
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with Republic Airways.
Republic on BWI to BOS carries a cancellation problem, not just a delay problem: 4.1% of scheduled flights never operate, against 1.9% nationally. Of the ones that do fly, about four flights in five arrive on time, worth a B− overall. The punctuality figure counts only flights that actually departed, so it flatters an operation that cancels this often. That rests on 1,099 flights, with a median arrival 12 minutes early.
The US average over the same twelve months is 77.3%, so there is little to separate Republic on BWI to BOS from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
80.5%
Arrivals under 15 minutes late, of 1,052 completed flights
Avg delay
85 min
Across delayed arrivals only, not all flights
Cancelled
4.09%
National rate is 1.89%
Whole route
74.1%
Every carrier on BWI to BOS, 3,540 flights
These figures cover 1,099 flights between September 2025 and August 2026. Beyond the headline rate, 8.9% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
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Carrier by carrier
Republic against every carrier on BWI to BOS
Republic flew 1,099 of the 3,540 flights on BWI to BOS, about 31% of it. Its 80.5% on time is 6 points better than the route as a whole, which runs 74.1%. Ranked by on-time rate it is number two of three carriers on the route, where the range runs from Spirit at 80.8% to Southwest at 71.1%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Spirit Airlinesthin sample | 26 | 80.8% | 35 min | 0.00% | B+ |
| Republic Airways (this page) | 1,099 | 80.5% | 85 min | 4.09% | B− |
| Southwest Airlines | 2,415 | 71.1% | 61 min | 2.77% | C |
Flight by flight
Republic flight numbers on BWI to BOS
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Departure window
When Republic runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 40 points, against half a point between the best and worst carrier.
- 5am–8am164 flights95.0%
- 8am–11am192 flights90.3%
- 11am–2pm243 flights79.1%
- 2pm–5pm161 flights82.1%
- 5pm–8pm178 flights55.2%
- 8pm–5am161 flights81.6%
Scale runs 45% to 100%.
The 5pm–8pm window is where this operation falls apart: 55.2% on time, against 95.0% 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 11am–2pm window is the busiest, with 243 flights scheduled in it.
Across the year
Republic on BWI to BOS through the year
Delays peak in September, when the on-time rate falls to 64.9%. March is the strongest month at 88.4%. Moving a flexible trip across that boundary buys 24 points. July was the busiest month here, with 112 flights.
Across the week, Saturday is the strongest day at 92.9% on time and Sunday the weakest at 74.6%, a spread of 18 points.
Arrival by arrival
How late Republic on BWI to BOS runs when it is late
Republic on BWI to BOS often beats the schedule: 459 of 1,052 completed flights, 44%, arrived 15 minutes or more early. The 205 late arrivals split 40 under half an hour, 71 between 30 and 60 minutes, and 94 an hour or more.
- 15+ min early459 flights43.6%
- Within 15 min388 flights36.9%
- 15–29 min late40 flights3.8%
- 30–59 min late71 flights6.7%
- 1–2 hours late57 flights5.4%
- 2+ hours late37 flights3.5%
Scale runs 0% to 100%.
Share of 1,052 completed flights by arrival against schedule.
24 of 186 late departures made up the time and arrived on time, 13% of them. 43 flights left on time and still arrived late.
The worst days
Worst days for Republic on BWI to BOS
The latest arrival of the period was on 1 April 2026, 15 hours 22 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on four of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 1 April 2026 | 15 hours 22 minutes | Carrier |
| 27 August 2026 | 12 hours 24 minutes | Carrier |
| 6 February 2026 | 11 hours 21 minutes | Carrier |
| 22 February 2026 | 4 hours 54 minutes | Late-arriving aircraft |
| 14 August 2026 | 4 hours 53 minutes | Carrier |
Delay causes
Why Republic runs late on this route
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 17,000 reported delay minutes.
- 40%National Airspace System
- 37%Carrier
- 22%Late-arriving aircraft
- 1%Extreme weather
- 0%Security
The largest share of delay minutes, 37%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 6,483 of the 17,000 delay minutes reported here. The split is drawn from 17,493 reported delay minutes.
40% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 6,948 minutes out of 17,000, against a national NAS share of 21%.
Cancellations run at 4.09%, against 1.89% nationally. That is about one flight in 25 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.
Connections and stage length
What a delay here costs
8.9% of arrivals land an hour or more late, close to the national 8.3%, so a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last an hour and a half, which a normal layover absorbs.
At 369 miles this is a short hop, and stage length matters more than it looks. A flight this short spends under two hours in the air, which leaves almost nothing to claw back a late pushback with. Delay here is decided on the ground, in the turn, which is why the 5am–8am window matters as much as it does.
The return leg runs 81.8% on time across 1,099 flights, within about a point 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 1,099 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.
What to do with this
Booking Republic on BWI to BOS
Put together: the delay figures matter less here than the 4.09% cancellation rate. A late arrival costs you an hour and a half; a cancelled flight costs you the day. Book the 5am–8am departure so there is still a schedule behind you if it goes wrong, and treat a same-day connection as optimistic. 1,052 completed flights over 12 months sit behind that.
Related
Where to go next
- BWI to BOS, every carrier
- Republic on BOS to BWI, the return leg
- Southwest Airlines on BWI to BOS71.1%
- Republic Airways network-wide record
- Baltimore/Washington International Thurgood Marshall (BWI) delay statistics
- Boston Logan International (BOS) delay statistics
- The US routes with the most cancellations
- The best time of day to fly, according to 7.05 million flight records
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.