Best time to fly out of Miami (MIA)

The early-flight folk wisdom holds up at Miami: departures in the 6–8am band left on time 90.7% of the time, against 65.1% in the 6–8pm band. These are historical odds, not forecasts. The records say what happened on this schedule over three years; they know nothing about tomorrow’s thunderstorm.

Data through June 2026 · Bureau of Transportation Statistics

On-time rate by hour and day

On this page, “on time” means a departure that pushed back less than 15 minutes behind its scheduled time — the Bureau of Transportation Statistics definition, and the one airlines are held to.

Share of departures that left on time, by hour band and day of week.
Departure time MonTueWedThuFriSatSun
Before 6am 88 91 91 92 91 90 87
6–8am 89 91 92 93 91 91 88
8–10am 86 89 89 88 88 87 84
10am–12pm 80 82 81 81 79 77 75
12–2pm 73 79 81 77 73 73 69
2–4pm 70 75 76 69 69 68 63
4–6pm 68 74 74 66 67 67 62
6–8pm 64 72 70 64 66 65 57
8–10pm 67 73 72 65 66 64 60
10pm–12am 71 78 75 67 69 69 59
fewer left on time more left on time

The steadiest stretch at MIA was 6–8am — 90.7% of departures left on time across 33,567 flights. The weakest was 6–8pm at 65.1%. 6–8am departures from MIA left on time 90.7% of the time across 33,567 flights; 6–8pm departures, 65.1% across 47,889. That is a gap of 25.6 points, and it is the whole case for the early flight.

The year at MIA

July was the hard month at MIA: 64.1% of departures left on time, across 26,435 flights. October was the easy one at 82.6%. Each month pools three years of that month, so a single bad week does not decide it.

Share of departures that left on time, by calendar month. Best month in green, worst in amber. The hairline sits at the overall rate, 74.2%.
Departure on-time share at MIA by calendar month
Month Share departures that left on time Flights
January 73.6% 30,835
February 77.8% 28,299
March 70.9% 31,913
April 77.2% 29,024
May 72.7% 28,239
June 69.3% 26,181
July 64.1% 26,435
August 67.3% 25,695
September 78% 22,730
October 82.6% 24,915
November 81.6% 27,103
December 75.1% 29,897

Airlines at MIA

Every airline with at least 100 departures from MIA, busiest first. These are that airline’s departures from this airport only — its record across the country sits on its own page.

Airline Left on time Typical delay Cancelled Departures
American Airlines 71.4% 75 min 1.4% 183,477
Envoy Air 84.7% 52 min 1.2% 41,637
Delta Air Lines 73.7% 82 min 1.4% 33,986
United Airlines 79.3% 86 min 1.6% 19,644
Southwest Airlines 72.7% 59 min 1.1% 16,920
Spirit Airlines 73.9% 77 min 2.4% 15,365
Frontier Airlines 76.1% 91 min 2.2% 11,846
JetBlue Airways 67.1% 98 min 2.5% 4,077
Republic Airways 78.2% 104 min 1.3% 2,691
Alaska Airlines 76.2% 67 min 2.5% 1,592

Spirit Airlines (through May 2026) stopped filing before June 2026. Its row covers a shorter run of months than the rest of the table, so its figure is not set against the others anywhere on this page.

What delays out of MIA were put down to

Airlines file a reason with every arrival running 15 minutes late or more. Across 86,443 flights that departed MIA and ran 15 minutes late or more, the delay minutes break down with 40.5% put down to late-arriving aircraft and 32.9% to airline operations.

Late-arriving aircraft 40.5% Airline operations 32.9% Air traffic & airport volume 20.6% Severe weather 5.7% Security 0.2%
  • Late-arriving aircraft 40.5%
  • Airline operations 32.9%
  • Air traffic & airport volume 20.6%
  • Severe weather 5.7%
  • Security 0.2%

Late-arriving aircraft is the knock-on category: the plane came in late, so it went out late again. It is why a 7am problem in Newark is still a problem in Denver at dinnertime, and why it is usually the biggest slice on the bar.

If you are connecting through MIA

Of 331,268 scheduled arrivals into MIA, 75.6% reached the gate less than 15 minutes behind schedule. Of the 74,700 arrivals that ran late, 52.7% were no more than 45 minutes behind — which is the difference between a tight connection and a new boarding pass.

Work out a specific layover — pick the airport and the minutes you have, and the tool reads the same arrival records back as a share.

Busiest routes out of MIA

Ranked by flights, with the share that arrived on time at the far end. Where a route carries enough flights for a page of its own the chip goes there; otherwise it goes to the destination airport.

MIA in one number

Miami (MIA)

Rank 21 of 363 US airports by departures. Steadiest stretch of the day: 6–8am. Hardest month: July.

July 2023–June 2026 · 326,375 departures flown

74.2% of departures left on time

Questions about MIA

What is the best time of day to fly out of Miami?
6–8am. Departures in that band left on time 90.7% of the time across 33,567 flights, July 2023 through June 2026 — the best of the ten bands in the day. The 6–8pm band was the weakest at 65.1%.
Is the early flight out of MIA really more reliable?
6–8am departures from MIA left on time 90.7% of the time across 33,567 flights; 6–8pm departures, 65.1% across 47,889. That is a gap of 25.6 points, and it is the whole case for the early flight.
What is the worst month to fly out of MIA?
July: 64.1% of the departures that flew left on time, with 26,435 scheduled. October was the other end of the year at 82.6%. Each figure pools three years of that calendar month.
Which airline is most on time at MIA?
Envoy Air — 84.7% of its 41,637 departures from MIA left on time. JetBlue Airways sat at the other end at 67.1% over 4,077 flights. Only airlines with at least 100 departures here are ranked. Airlines that stopped filing before June 2026 are left out of the ranking — their figures cover a shorter run of months than the rest of the table.
How often are flights cancelled at MIA?
1.5% of scheduled departures were cancelled over July 2023 through June 2026. Cancellations are counted against everything scheduled, not against everything that flew — a rate that looks small still adds up to real people in a rebooking line.