Route reliability record

RSW→BOS

Fort Myers to Boston

Flights: 2,254
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 an hour and a half behind schedule. That rests on 2,254 flights, of which Delta Air Lines flew 582 at 75.8% 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 72 extra late arrivals.

On time

70.4%

Arrivals under 15 minutes late, of 2,191 completed flights

Avg delay

84 min

Across delayed arrivals only, not all flights

Cancelled

2.80%

National rate is 1.81%

Best carrier

Delta

75.8% on time across 582 flights

These figures cover 2,254 flights between July 2025 and June 2026. Beyond the headline rate, 12.1% 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 RSW to BOS

The two carriers here are closely matched: 6 points separate the best from the worst. At that spread, schedule and price are better tie-breakers than reliability. Sample sizes are shown so you can see which rows are worth weighing.

On-time performance by carrier on RSW to BOS
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines	582	75.8%	78 min	1.37%	B
JetBlue Airways	1,596	69.9%	86 min	2.88%	C
Spirit Airlinesthin sample	76	34.3%	72 min	11.84%	F−

No carrier stands out. Delta tops the table at 75.8%, 6 points clear of the bottom, which is inside the range this kind of sample moves year to year.

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 36 points, against 6 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am387 flights89.9%
8am–11am331 flights79.6%
11am–2pm586 flights72.9%
2pm–5pm273 flights57.0%
5pm–8pm374 flights54.4%
8pm–5am303 flights61.8%

Scale runs 45% to 95%. Rows with fewer than 30 flights show a dash.

The 5pm–8pm window is where this operation falls apart: 54.4% on time, against 89.9% 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 586 flights scheduled in it.

Across the year

When delays peak on this route

This route's year swings by 25 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.August best, March worst

Delays peak in March, when the on-time rate falls to 60.8%. August is the strongest month at 85.6%. Moving a flexible trip across that boundary buys 25 points. March was the busiest month here, with 326 flights.

Across the week, Wednesday is the strongest day at 76.7% on time and Thursday the weakest at 65.7%. 11 points is a smaller lever than departure hour, but it is free.

Delay causes

Why this route gets delayed

One category carries most of the weight here. Late-arriving aircraft accounts for 43% of the 54,000 delay minutes carriers reported, and the remaining four split what is left. The split is by minutes rather than by flights, so a few very long delays count for as much as many short ones.

Late-arriving aircraft
43%
Carrier
28%
National Airspace System
26%
Extreme weather
3%
Security
0%

43% 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 54,000 reported delay minutes here, that single category outweighs weather by 16 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 54,256 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 89.9% on time here.

Cancellations run at 2.80%, against 1.81% nationally. That is roughly 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. 12.1% 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 70.5% on time across 2,253 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 2,254 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 delay figures matter less here than the 2.80% 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. 2,191 completed flights over 12 months sit behind that.

Common questions

RSW to BOS questions

How often is RSW to BOS 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 29.6% of the 2,254 flights in this analysis, against 22.4% nationally. Delayed flights are late by an hour and a half on average.

Which airline is most reliable on RSW to BOS?

Delta Air Lines leads at 75.8% on time across 582 flights. JetBlue Airways is at the other end on 69.9%, a gap of 6 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 RSW to BOS?

The 5am–8am departure window is the strongest at 89.9% on time. The 5pm–8pm window is the weakest at 54.4%, 36 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 March delays on RSW to BOS?

March is the weakest month at 60.8% on time, compared with 85.6% in August. Across the year that is 25 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. RSW to BOS and BOS to RSW 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