Flight number record

DL 2631

Delta Air Lines · Fort Lauderdale to Detroit

Route: FLL → DTW
Departs: 06:00
Flights: 365
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 2631, check with Delta Air Lines.

DL 2631 earns an A. Close to nine flights in ten arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 15 points better than the national rate of 77.6%. When something does go wrong the average delay runs an hour and a half. That rests on 365 flights, with a median arrival 10 minutes early.

Set against the rest of the country, DL 2631's record is 15 points better than the US average of 77.6%. That gap is worth roughly 149 fewer late arrivals for every thousand flights.

On time

92.5%

Arrivals under 15 minutes late, of 360 completed flights

Avg delay

89 min

Across delayed arrivals only, not all flights

Cancelled

1.37%

National rate is 1.81%

1 hour+ late

3.1%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 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.

Schedule

When DL 2631 flies

DL 2631 flies FLL to DTW without a single fixed slot. Its most common scheduled departure was 06:00, used on 265 of 365 flights, with 06:30 (53 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 06:00265 flights72.6%
Departs 06:3053 flights14.5%

Scale runs 0% to 100%. Rows with fewer than 30 flights show a dash.

Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.

A 06:00 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and DL 2631 runs 3 points better at 92.5%. Early departures usually start with an aircraft that has not flown yet that day, which is most of why the window does well.

Against the route

DL 2631 next to FLL to DTW

Every carrier on FLL to DTW combined arrived on time 73.2% of the time across 2,719 flights, so DL 2631 is 19 points ahead of it. Delta flew 1,817 flights on the same city pair under all its flight numbers, including this one, and those ran 79.3% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 11 points.

DL 2631 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 2631	365	92.5%	89 min	1.37%	A
All Delta Air Lines on FLL–DTW	1,817	79.3%	75 min	1.27%	B
All carriers on FLL–DTW	2,719	73.2%	76 min	1.80%	C
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 2631 quarter by quarter

DL 2631 did not run the same all year. Its best quarter was Jul–Sep 2025 at 97.8% on time and its weakest Oct–Dec 2025 at 85.6%, a swing of 12 points on roughly 91 flights a quarter. The twelve-month rate averages over that, so if you are flying in a weak quarter the quarter's own figure is the better guide.

Jul–Sep 202592 flights97.8%
Oct–Dec 202592 flights85.6%
Jan–Mar 202690 flights88.6%
Apr–Jun 202691 flights97.8%

Scale runs 75% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, DL 2631 ranged from 90.0% on Tuesday to 94.2% on Friday. With about 52 flights behind each day, a spread of 4 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why DL 2631 runs late

One category carries most of the weight here. Carrier accounts for 60% of the 2,412 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.

Carrier
60%
Late-arriving aircraft
32%
National Airspace System
9%

The largest share of delay minutes, 60%, 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 1,439 of the 2,412 delay minutes reported here. The split is drawn from 2,412 delay minutes reported on DL 2631.

Cancellations sit at 1.37% against a national 1.81%, which is ordinary. Diversions add another 0.00%.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 3.1% land an hour or more behind schedule, against 8.1% 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.

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.

Every one of the 365 flights under DL 2631 in the data flew FLL to DTW. The number was not reused on any other city pair, which makes this a clean record of one route.

One caution: this is a thin sample. 365 flights over twelve months is enough to clear this site's floor but not enough to pin the rate down tightly, and a single bad week moves it by more than a point. Treat the grade as a rough reading.

What to do with this

Booking DL 2631

For a booking, DL 2631 has one of the better records a US domestic flight can show: 92.5% on time and 1.37% cancelled. That is a base rate, not a promise about any single day.

Where to go next

A flight number here means Delta Air Lines’s own number as it reports to the DOT. How the figures are computed is on the methodology page.

Source: US DOT Bureau of Transportation Statistics, on-time performance data, July 2025 to June 2026. Last updated 15 September 2026; recomputed monthly. How this data is collected.

Key figures