Flight number record

DL 2508

Delta Air Lines · Seattle to San Diego

Route: SEA → SAN
Departs: 07:10
Flights: 349
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 2508, check with Delta Air Lines.

DL 2508 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 14 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 349 flights, with a median arrival 12 minutes early.

Set against the rest of the country, DL 2508's record is 14 points better than the US average of 77.6%. That gap is worth roughly 140 fewer late arrivals for every thousand flights.

On time

91.6%

Arrivals under 15 minutes late, of 344 completed flights

Avg delay

60 min

Across delayed arrivals only, not all flights

Cancelled

0.86%

National rate is 1.81%

1 hour+ late

3.2%

National rate is 8.1%

These figures cover 349 flights between July 2025 and June 2026. The median arrival is 12 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 2508 flies

DL 2508 flies SEA to SAN without a single fixed slot. Its most common scheduled departure was 07:10, used on 131 of 349 flights, with 07:15 (88 flights) and 07:20 (70 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 07:10131 flights37.5%
Departs 07:1588 flights25.2%
Departs 07:2070 flights20.1%

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 07:10 departure sits in the 5am–8am window. Across every US flight scheduled in that window the on-time rate is 89.3%, and DL 2508 runs 2 points better at 91.6%. 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 2508 next to SEA to SAN

Every carrier on SEA to SAN combined arrived on time 77.3% of the time across 4,584 flights, so DL 2508 is 14 points ahead of it. Delta flew 1,700 flights on the same city pair under all its flight numbers, including this one, and those ran 82.6% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 10 points.

DL 2508 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 2508thin sample	349	91.6%	60 min	0.86%	A+
All Delta Air Lines on SEA–SAN	1,700	82.6%	53 min	0.94%	B+
All carriers on SEA–SAN	4,584	77.3%	46 min	1.22%	B
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 2508 quarter by quarter

DL 2508 did not run the same all year. Its best quarter was Jul–Sep 2025 at 96.7% on time and its weakest Oct–Dec 2025 at 84.1%, a swing of 13 points on roughly 87 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 flights96.7%
Oct–Dec 202582 flights84.1%
Jan–Mar 202684 flights90.2%
Apr–Jun 202691 flights94.4%

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

By weekday, DL 2508 did best on Tuesday at 98.1% on time and worst on Monday at 84.0%. Each day rests on about 50 flights, so a gap of 14 points is worth noticing but could still narrow in another year.

Delay causes

Why DL 2508 runs late

One category carries most of the weight here. Carrier accounts for 67% of the 1,741 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
67%
National Airspace System
25%
Late-arriving aircraft
4%
Extreme weather
4%

The largest share of delay minutes, 67%, 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 1,166 of the 1,741 delay minutes reported here. The split is drawn from 1,741 delay minutes reported on DL 2508.

Cancellations are rare at 0.86%, 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 3.2% 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 1,050 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.

DL 2508 is not only a SEA to SAN flight. It also flew SAN to SEA (349 flights, 89.6% on time) often enough to be scored on its own. Airlines attach one number to several legs of an aircraft's day, and each leg keeps its own record here, so check which city pair is on your booking before reading a rate.

One caution: this is a thin sample. 349 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.

Other routes flown as DL 2508
Also flown as	Flights	On time	Avg delay	Cancelled	Grade
SAN to SEAthin sample	349	89.6%	79 min	0.86%	A+

What to do with this

Booking DL 2508

For a booking, DL 2508 has one of the better records a US domestic flight can show: 91.6% on time and 0.86% 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