Flight number record

DL 2663

Delta Air Lines · Denver to Salt Lake City

Route: DEN → SLC
Departs: 18:23
Flights: 365
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 2663, check with Delta Air Lines.

DL 2663 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 about an hour behind schedule. That rests on 365 flights, with a median arrival 3 minutes late.

The national on-time rate over the same period is 77.6%, so DL 2663 runs 9 points behind the country as a whole. Across a thousand flights that is about 86 extra late arrivals.

On time

69.0%

Arrivals under 15 minutes late, of 364 completed flights

Avg delay

61 min

Across delayed arrivals only, not all flights

Cancelled

0.00%

National rate is 1.81%

1 hour+ late

9.9%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 2026. Beyond the headline rate, 9.9% 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 2663 flies

DL 2663 flies DEN to SLC without a single fixed slot. Its most common scheduled departure was 18:23, used on 78 of 365 flights, with 18:25 (63 flights) and 18:20 (48 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 18:2378 flights21.4%
Departs 18:2563 flights17.3%
Departs 18:2048 flights13.2%

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 18:23 departure sits in the 5pm–8pm window. Across every US flight scheduled in that window the on-time rate is 68.2%, and DL 2663 runs level with that at 69.0%. 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 2663 next to DEN to SLC

Every carrier on DEN to SLC combined arrived on time 77.5% of the time across 7,758 flights, so DL 2663 is 9 points behind it. Delta flew 1,689 flights on the same city pair under all its flight numbers, including this one, and those ran 82.3% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight trails by 13 points.

DL 2663 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 2663	365	69.0%	61 min	0.00%	C+
All Delta Air Lines on DEN–SLC	1,689	82.3%	81 min	0.41%	B+
All carriers on DEN–SLC	7,758	77.5%	61 min	0.48%	B+
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 2663 quarter by quarter

Quarter by quarter DL 2663 held fairly steady: 64.1% in Jul–Sep 2025, 71.4% in Oct–Dec 2025, 70.0% in Jan–Mar 2026 and 70.3% in Apr–Jun 2026. A spread of 7 points is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights64.1%
Oct–Dec 202592 flights71.4%
Jan–Mar 202690 flights70.0%
Apr–Jun 202691 flights70.3%

Scale runs 55% to 75%. Rows with fewer than 30 flights show a dash.

By weekday, DL 2663 did best on Tuesday at 73.6% on time and worst on Sunday at 61.5%. Each day rests on about 52 flights, so a gap of 12 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 2663 runs late

One category carries most of the weight here. Late-arriving aircraft accounts for 67% of the 6,841 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
67%
Carrier
22%
National Airspace System
10%
Extreme weather
1%

67% 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 6,841 reported delay minutes here, that single category outweighs weather by 67 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 6,841 delay minutes reported on DL 2663.

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. 9.9% 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 365 flights under DL 2663 in the data flew DEN to SLC. 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 2663

For a booking, DL 2663 is one of the weaker ways to fly DEN to SLC: 9 points below the route as a whole. If the schedule allows, compare it with the other departures listed on the route page before settling on this one.

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