Route reliability record
MIA→EYW
Miami to Key West
- Flights
- 1,274
- Period
- September 2025 to August 2026
- Distance
- 126 mi
- Carriers
- 3
This route earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 10 points better than the national rate of 77.3%. When something does go wrong the average delay runs about 50 minutes. That rests on 1,274 MIA to EYW flights, with a median arrival 10 minutes early.
Best time to fly MIA to EYW: a 8pm–5am departure, ideally on a Tuesday. Flights in that window arrived on time 95.3% of the time and Tuesday flights 92.1%, against 86.8% for the route overall.
Set against the rest of the country, this route's record is 10 points better than the US average of 77.3%. That gap is worth roughly 95 fewer late arrivals for every thousand flights.
Key figures
On time
86.8%
Arrivals under 15 minutes late, of 1,264 completed flights
Avg delay
51 min
Across delayed arrivals only, not all flights
Cancelled
0.39%
National rate is 1.89%
Best carrier
Envoy
88.3% on time across 1,179 flights
These figures cover 1,274 flights between September 2025 and August 2026. The median arrival is 10 minutes early, which is the part an average hides: most flights here are fine, and the on-time rate is decided by a tail of badly late ones. On-time means under 15 minutes late, the DOT's own threshold.
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Carrier by carrier
Which airline is most reliable on MIA to EYW
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 |
|---|---|---|---|---|---|
| Envoy Air | 1,179 | 88.3% | 48 min | 0.42% | A+ |
| American Airlinesthin sample | 25 | 76.0% | 74 min | 0.00% | B+ |
| Republic Airwaysthin sample | 70 | 65.2% | 59 min | 0.00% | C+ |
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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 14 points, against half a point between the best and worst carrier.
- 5am–8am—
- 8am–11am334 flights91.0%
- 11am–2pm287 flights81.1%
- 2pm–5pm230 flights86.0%
- 5pm–8pm316 flights85.2%
- 8pm–5am107 flights95.3%
Scale runs 75% to 100%. Rows with fewer than 30 flights show a dash.
The weak window here is the middle of the day, not the evening: 11am–2pm runs 81.1% on time against 95.3% for 8pm–5am. That shape usually means a departure bank rather than an accumulating delay, so the recovery later in the afternoon is real rather than noise. The 8am–11am window is the busiest, with 334 flights scheduled in it.
Explore
Filter MIA to EYW by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On MIA to EYW, the best departure window is 8pm–5am at 95.3% on time and the worst is 11am–2pm at 81.1%, a wide gap of 14.2 points. All US flights leaving 8pm–5am ran 70.1%.
- 5–8am—
- 8–11am91.0%
- 11am–2pm81.1%
- 2–5pm86.0%
- 5–8pm85.2%
- 8pm–5am95.3%
best all US flightsScale 60% to 100%. Cells under 30 flights show a dash.
Across the year
When delays peak on this route
This route's year swings by 19 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.
February is the weak month at 75.2% on time, against 93.8% in May. 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. January was the busiest month here, with 150 flights.
Across the week, Tuesday is the strongest day at 92.1% on time and Saturday the weakest at 75.5%, a spread of 17 points.
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 8,468 reported delay minutes.
- 39%Late-arriving aircraft
- 25%National Airspace System
- 19%Carrier
- 16%Extreme weather
Extreme weather accounts for 16% of delay minutes, well above the single-digit share typical across the system. Weather delays are lumpy: they arrive as whole bad days rather than as a steady drag, so the monthly strip above is the more useful view of the risk. The national share is 6%, so this operation carries roughly 2.7 times the usual weather exposure. The split is drawn from 8,468 reported delay minutes.
39% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 8,468 reported delay minutes here, that single category outweighs weather by 2 to one.
Cancellations are rare at 0.39%, below the national 1.89% 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.
Connections and stage length
What a delay here actually costs
Badly late arrivals are rare here: only 3.1% land an hour or more behind schedule, against 8.3% nationally. Connections built on this flight are about as safe as US domestic connections get, though a cancelled flight still ignores every layover you give it.
At 126 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 8pm–5am window matters as much as it does.
The return leg is a different operation and performs like one: it runs 81.7% on time across 1,274 flights, 5 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 5 points of difference.
The sample behind these figures is 1,274 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.
Work out the risk of missing a connection in EYW after this flight
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. May runs 93.8% on time and February 75.2%, a swing of 19 points. If the dates move at all, move them out of February before you think about anything else. 1,264 completed flights over 12 months sit behind that.
Common questions
MIA to EYW questions
How often is MIA to EYW delayed?
About one flight in eight arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 13.2% of the 1,274 flights in this analysis, against 22.7% nationally. Delayed flights are late by about 50 minutes on average.
How reliable is MIA to EYW compared with the rest of the country?
86.8% of flights arrive on time here against a national 77.3%, a difference of 10 points in its favour. That is worth a A+ on this site's grading scale.
What time of day has the fewest delays on MIA to EYW?
The 8pm–5am departure window is the strongest at 95.3% on time. The 11am–2pm window is the weakest at 81.1%, 14 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 February delays on MIA to EYW?
February is the weakest month at 75.2% on time, compared with 93.8% in May. Across the year that is 19 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- EYW to MIA — the return legseparate record
- Miami International (MIA) delay statistics
- MIA to ATL, a related route74.2%
- ATL to EYW, a related route83.0%
- MIA to LGA, a related route67.4%
- Envoy Air on-time record88.3%
- American Airlines on-time record76.0%
- Republic Airways on-time record65.2%
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.05 million flight records
Direction matters. MIA to EYW and EYW to MIA are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
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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.