Route reliability record

BOS→RSW

Boston to Fort Myers

Flights: 2,253
Period: July 2025 to June 2026
Distance: 1,249 mi
Carriers: 3

This route sits in the middle of the pack with a C. About seven flights in ten arrive on time by the DOT's definition, 7 points worse than the national rate of 77.6%. The late ones land about an hour behind schedule. That rests on 2,253 flights, of which Delta Air Lines flew 582 at 77.5% on time.

The national on-time rate over the same period is 77.6%, so this route runs 7 points behind the country as a whole. Across a thousand flights that is about 71 extra late arrivals.

On time

70.5%

Arrivals under 15 minutes late, of 2,185 completed flights

Avg delay

66 min

Across delayed arrivals only, not all flights

Cancelled

2.62%

National rate is 1.81%

Best carrier

Delta

77.5% on time across 582 flights

These figures cover 2,253 flights between July 2025 and June 2026. Beyond the headline rate, 10.8% of arrivals land a full hour or more behind schedule. That is the number that wrecks a connection, and it is not visible in an on-time percentage alone.

Carrier by carrier

Which airline is most reliable on BOS to RSW

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 77.5% of the time; JetBlue Airways manages 69.4%. Sample sizes sit next to every figure, because a two-point gap across 1,596 flights means less than a ten-point one.

On-time performance by carrier on BOS to RSW
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines	582	77.5%	64 min	1.55%	B
JetBlue Airways	1,596	69.4%	67 min	2.63%	C
Spirit Airlinesthin sample	75	34.3%	52 min	10.67%	F−

Delta leads JetBlue by 8 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.

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 25 points, against 8 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am692 flights85.3%
8am–11am201 flights75.6%
11am–2pm316 flights66.2%
2pm–5pm594 flights60.3%
5pm–8pm299 flights62.1%
8pm–5am151 flights61.1%

Scale runs 50% to 90%. Rows with fewer than 30 flights show a dash.

Book the early departure. Flights leaving between 5am–8am arrive on time 85.3% of the time, against 60.3% for the afternoon window. That is 25 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 692 flights scheduled in it.

Across the year

When delays peak on this route

This route's year swings by 28 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.

Darker means more delays. Figures are on-time percentages.June best, January worst

January is the weak month at 56.8% on time, against 84.5% in June. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. March was the busiest month here, with 326 flights.

Across the week, Wednesday is the strongest day at 80.2% on time and Sunday the weakest at 61.2%. 19 points is a smaller lever than departure hour, but it is free.

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 42,000 reported delay minutes.

Late-arriving aircraft
40%
Carrier
30%
National Airspace System
28%
Extreme weather
3%
Security
0%

40% 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 42,000 reported delay minutes here, that single category outweighs weather by 15 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 42,363 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 85.3% on time here.

Cancellations run at 2.62%, against 1.81% nationally. That is about one flight in 40 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 actually costs

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 10.8% of arrivals land a full hour or more behind schedule, against 8.1% nationally. A 45-minute layover does not survive that, and no amount of walking quickly changes it. Ninety minutes is the honest minimum here, and two hours if the onward flight is on a separate ticket.

The 1,249 miles between these two airports put this in the middle of the US network, around two and a half to three hours of block time. That is enough cruise to absorb a ten-minute late pushback and not enough to absorb thirty. It is also long enough that the aircraft usually flies three or four legs a day rather than six, which slows how fast delay compounds.

The return leg runs 70.4% on time across 2,254 flights, within half 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 2,253 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 this route

Put together: the calendar is the biggest lever here, not the carrier or the hour. June runs 84.5% on time and January 56.8%, a swing of 28 points. If the dates move at all, move them out of January before you think about anything else. 2,185 completed flights over 12 months sit behind that.

Common questions

BOS to RSW questions

How often is BOS to RSW delayed?

Roughly one flight in three arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 29.5% of the 2,253 flights in this analysis, against 22.4% nationally. Delayed flights are late by about an hour on average.

Which airline is most reliable on BOS to RSW?

Delta Air Lines leads at 77.5% on time across 582 flights. JetBlue Airways is at the other end on 69.4%, a gap of 8 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 BOS to RSW?

The 5am–8am departure window is the strongest at 85.3% on time. The 2pm–5pm window is the weakest at 60.3%, 25 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 January delays on BOS to RSW?

January is the weakest month at 56.8% on time, compared with 84.5% in June. Across the year that is 28 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.

Where to go next

Direction matters. BOS to RSW and RSW to BOS are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Updated monthly. How this data is collected.

Key figures