Route reliability record

FLL→DTW

Fort Lauderdale to Detroit

Flights: 2,719
Period: July 2025 to June 2026
Distance: 1,127 mi
Carriers: 3

This route sits in the middle of the pack with a C. Close to three flights in four arrive on time by the DOT's definition, 4 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 2,719 flights, of which Delta Air Lines flew 1,817 at 79.3% on time.

The national on-time rate over the same period is 77.6%, so this route runs 4 points behind the country as a whole. Across a thousand flights that is about 44 extra late arrivals.

On time

73.2%

Arrivals under 15 minutes late, of 2,665 completed flights

Avg delay

76 min

Across delayed arrivals only, not all flights

Cancelled

1.80%

National rate is 1.81%

Best carrier

Delta

79.3% on time across 1,817 flights

These figures cover 2,719 flights between July 2025 and June 2026. Beyond the headline rate, 11.3% 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 FLL to DTW

The choice of carrier is not cosmetic here. Delta Air Lines arrives on time 79.3% of the time; Spirit Airlines manages 62.4%. Sample sizes sit next to every figure, because a two-point gap across 813 flights means less than a ten-point one.

On-time performance by carrier on FLL to DTW
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines	1,817	79.3%	75 min	1.27%	B
Spirit Airlines	813	62.4%	75 min	2.58%	D
Frontier Airlinesthin sample	89	46.4%	91 min	5.62%	F−

The spread between Delta and Spirit is 17 points, wide enough that it should decide the booking. On a hundred trips that is 17 more arrivals inside the on-time window.

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 35 points, against 17 points between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.

5am–8am583 flights90.3%
8am–11am142 flights87.0%
11am–2pm527 flights77.5%
2pm–5pm610 flights72.2%
5pm–8pm332 flights59.9%
8pm–5am525 flights55.8%

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

The 8pm–5am window is where this operation falls apart: 55.8% on time, against 90.3% 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 2pm–5pm window is the busiest, with 610 flights scheduled in it.

Across the year

When delays peak on this route

This route's year swings by 33 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, March worst

Delays peak in March, when the on-time rate falls to 57.1%. June is the strongest month at 90.6%. Moving a flexible trip across that boundary buys 33 points. March was the busiest month here, with 328 flights.

Across the week, Wednesday is the strongest day at 82.7% on time and Sunday the weakest at 59.8%. 23 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
37%
National Airspace System
18%
Extreme weather
2%
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 22 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 54,105 reported delay minutes.

The largest share of delay minutes, 37%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. Unlike weather, that is a management outcome, and it is the category where the gap between two carriers on the same schedule is genuinely earned. It accounts for 20,000 of the 54,000 delay minutes reported here.

Cancellations sit at 1.80% against a national 1.81%, which is ordinary. Diversions add another 0.18%.

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. 11.3% 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 1,127 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 72.4% on time across 2,706 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 2,719 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 90.6% on time and March 57.1%, a swing of 33 points. If the dates move at all, move them out of March before you think about anything else. 2,665 completed flights over 12 months sit behind that.

Common questions

FLL to DTW questions

How often is FLL to DTW delayed?

About one flight in four arrive at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 26.8% of the 2,719 flights in this analysis, against 22.4% nationally. Delayed flights are late by a little over an hour on average.

Which airline is most reliable on FLL to DTW?

Delta Air Lines leads at 79.3% on time across 1,817 flights. Spirit Airlines is at the other end on 62.4%, a gap of 17 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 FLL to DTW?

The 5am–8am departure window is the strongest at 90.3% on time. The 8pm–5am window is the weakest at 55.8%, 35 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 FLL to DTW?

March is the weakest month at 57.1% on time, compared with 90.6% in June. Across the year that is 33 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. FLL to DTW and DTW to FLL 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