Flight number record

DL 1586

Delta Air Lines · Salt Lake City to Denver

Route: SLC → DEN
Departs: 18:25
Flights: 343
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 1586, check with Delta Air Lines.

DL 1586 sits in the middle of the pack with a C+. About seven flights in ten arrive on time by the DOT's definition, 9 points worse than the national rate of 77.6%. The late ones land a little over an hour behind schedule. That rests on 343 flights, with a median arrival 4 minutes early.

The national on-time rate over the same period is 77.6%, so DL 1586 runs 9 points behind the country as a whole. Across a thousand flights that is about 94 extra late arrivals.

On time

68.2%

Arrivals under 15 minutes late, of 343 completed flights

Avg delay

75 min

Across delayed arrivals only, not all flights

Cancelled

0.00%

National rate is 1.81%

1 hour+ late

13.4%

National rate is 8.1%

These figures cover 343 flights between July 2025 and June 2026. Beyond the headline rate, 13.4% 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.

Schedule

When DL 1586 flies

DL 1586 flies SLC to DEN without a single fixed slot. Its most common scheduled departure was 18:25, used on 82 of 343 flights, with 17:30 (63 flights) and 18:15 (43 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 18:2582 flights23.9%
Departs 17:3063 flights18.4%
Departs 18:1543 flights12.5%

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 18:25 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.2%, and DL 1586 runs level with that at 68.2%. By that time of day most aircraft have flown several legs already, and whatever went wrong earlier is still in the schedule.

Against the route

DL 1586 next to SLC to DEN

Every carrier on SLC to DEN combined arrived on time 77.8% of the time across 7,757 flights, so DL 1586 is 10 points behind it. Delta flew 1,690 flights on the same city pair under all its flight numbers, including this one, and those ran 79.4% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight trails by 13 points.

DL 1586 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 1586thin sample	343	68.2%	75 min	0.00%	C+
All Delta Air Lines on SLC–DEN	1,690	79.4%	64 min	0.24%	B+
All carriers on SLC–DEN	7,757	77.8%	61 min	0.55%	B+
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 1586 quarter by quarter

DL 1586 did not run the same all year. Its best quarter was Apr–Jun 2026 at 78.2% on time and its weakest Jul–Sep 2025 at 48.8%, a swing of 29 points on roughly 86 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 202586 flights48.8%
Oct–Dec 202581 flights74.1%
Jan–Mar 202689 flights71.9%
Apr–Jun 202687 flights78.2%

Scale runs 40% to 85%. Rows with fewer than 30 flights show a dash.

By weekday, DL 1586 did best on Sunday at 78.0% on time and worst on Thursday at 54.9%. Each day rests on about 49 flights, so a gap of 23 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 1586 runs late

One category carries most of the weight here. Carrier accounts for 53% of the 8,167 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
53%
Late-arriving aircraft
25%
National Airspace System
22%

The largest share of delay minutes, 53%, 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 4,295 of the 8,167 delay minutes reported here. The split is drawn from 8,167 delay minutes reported on DL 1586.

Cancellations are rare at 0.00%, below the national 1.81% and low enough to earn the plus on the grade. Almost no flights are called off; the risk here is arriving late, not not arriving.

Connections and routes

What a delay on this flight costs

For anyone connecting, the number to weigh is not the on-time rate but the tail behind it. 13.4% 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.

Every one of the 343 flights under DL 1586 in the data flew SLC to DEN. 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. 343 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 1586

For a booking, DL 1586 is a flight to put a long connection behind. 13.4% of its completed flights arrived an hour or more late, which a short layover will not absorb. If the onward flight is on a separate ticket, the risk sits with you.

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