Flight number record

DL 2921

Delta Air Lines · Salt Lake City to Seattle

Route: SLC → SEA
Departs: 13:25
Flights: 287
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 2921, check with Delta Air Lines.

DL 2921 earns a B+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 7 points better than the national rate of 77.6%. When something does go wrong the average delay runs about 55 minutes. That rests on 287 flights, with a median arrival 8 minutes early.

Set against the rest of the country, DL 2921's record is 7 points better than the US average of 77.6%. That gap is worth roughly 70 fewer late arrivals for every thousand flights.

On time

84.6%

Arrivals under 15 minutes late, of 285 completed flights

Avg delay

54 min

Across delayed arrivals only, not all flights

Cancelled

0.70%

National rate is 1.81%

1 hour+ late

3.9%

National rate is 8.1%

These figures cover 287 flights between July 2025 and June 2026. The median arrival is 8 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 2921 flies

DL 2921 flies SLC to SEA without a single fixed slot. Its most common scheduled departure was 13:25, used on 93 of 287 flights, with 13:40 (72 flights) and 13:20 (45 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 13:2593 flights32.4%
Departs 13:4072 flights25.1%
Departs 13:2045 flights15.7%

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 13:25 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.8%, and DL 2921 runs 6 points better at 84.6%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

DL 2921 next to SLC to SEA

Every carrier on SLC to SEA combined arrived on time 80.2% of the time across 4,108 flights, so DL 2921 is 4 points ahead of it. Delta flew 2,222 flights on the same city pair under all its flight numbers, including this one, and those ran 83.3% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 3 points.

DL 2921 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 2921thin sample	287	84.6%	54 min	0.70%	B+
All Delta Air Lines on SLC–SEA	2,222	83.3%	54 min	0.54%	B+
All carriers on SLC–SEA	4,108	80.2%	53 min	0.97%	B+
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 2921 quarter by quarter

DL 2921 did not run the same all year. Its best quarter was Apr–Jun 2026 at 89.0% on time and its weakest Oct–Dec 2025 at 74.0%, a swing of 15 points on roughly 96 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 202590 flights86.7%
Oct–Dec 202578 flights74.0%
Jan–Mar 202628 flights—
Apr–Jun 202691 flights89.0%

Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.

By weekday, DL 2921 did best on Saturday at 95.1% on time and worst on Monday at 75.0%. Each day rests on about 41 flights, so a gap of 20 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 2921 runs late

One category carries most of the weight here. Carrier accounts for 48% of the 2,394 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
48%
Late-arriving aircraft
38%
National Airspace System
15%

38% 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 2,394 reported delay minutes here, that single category outweighs weather by 38 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 2,394 delay minutes reported on DL 2921.

Cancellations are rare at 0.70%, 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 3.9% 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 689 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 287 flights under DL 2921 in the data flew SLC to SEA. 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. 287 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 2921

For a booking, read DL 2921 as 84.6% on time with 0.70% cancelled over 287 flights. Those are rates from the past twelve months, not a forecast for any particular 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