Flight number record

DL 1331

Delta Air Lines · San Francisco to Salt Lake City

Route: SFO → SLC
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 1331, check with Delta Air Lines.

DL 1331 earns an A+. Nearly every flight arrives inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 19 points better than the national rate of 77.6%. When something does go wrong the average delay runs about 2.4 hours. That rests on 365 flights, with a median arrival 15 minutes early.

Set against the rest of the country, DL 1331's record is 19 points better than the US average of 77.6%. That gap is worth roughly 191 fewer late arrivals for every thousand flights.

On time

96.7%

Arrivals under 15 minutes late, of 363 completed flights

Avg delay

145 min

Across delayed arrivals only, not all flights

Cancelled

0.55%

National rate is 1.81%

1 hour+ late

1.9%

National rate is 8.1%

These figures cover 365 flights between July 2025 and June 2026. The median arrival is 15 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 1331 flies

DL 1331 flies SFO to SLC without a single fixed slot. Its most common scheduled departure was 06:00, used on 107 of 365 flights, with 05:35 (92 flights) and 05:40 (91 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 06:00107 flights29.3%
Departs 05:3592 flights25.2%
Departs 05:4091 flights24.9%

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 1331 runs 7 points better at 96.7%. 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 1331 next to SFO to SLC

Every carrier on SFO to SLC combined arrived on time 77.2% of the time across 3,471 flights, so DL 1331 is 20 points ahead of it. Delta flew 1,708 flights on the same city pair under all its flight numbers, including this one, and those ran 78.1% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 15 points.

DL 1331 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 1331	365	96.7%	145 min	0.55%	A+
All Delta Air Lines on SFO–SLC	1,708	78.1%	77 min	0.88%	B+
All carriers on SFO–SLC	3,471	77.2%	70 min	0.89%	B+
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 1331 quarter by quarter

Quarter by quarter DL 1331 held fairly steady: 96.7% in Jul–Sep 2025, 96.7% in Oct–Dec 2025, 96.6% in Jan–Mar 2026 and 96.7% in Apr–Jun 2026. A spread of half a point is about what a sample of this size moves on its own, so the annual figure is a fair summary.

Jul–Sep 202592 flights96.7%
Oct–Dec 202592 flights96.7%
Jan–Mar 202690 flights96.6%
Apr–Jun 202691 flights96.7%

Scale runs 90% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, DL 1331 ranged from 90.6% on Tuesday to 100.0% on Thursday. With about 52 flights behind each day, a spread of 9 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why DL 1331 runs late

One category carries most of the weight here. Carrier accounts for 49% of the 1,744 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
49%
Late-arriving aircraft
46%
National Airspace System
4%

46% 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 1,744 reported delay minutes here, that single category outweighs weather by 46 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 1,744 delay minutes reported on DL 1331.

Cancellations are rare at 0.55%, below the national 1.81% and low enough to earn the plus on the grade. Roughly one flight in 100 is called off; the risk here is arriving late, not not arriving.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 1.9% 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 599 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 1331 in the data flew SFO 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 1331

For a booking, DL 1331 has one of the better records a US domestic flight can show: 96.7% on time and 0.55% 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