Flight number record

DL 533

Delta Air Lines · Seattle to Detroit

Route: SEA → DTW
Departs: 15:15
Flights: 316
Period: July 2025 to June 2026

Historical statistics for July 2025 to June 2026, not live status. For today’s DL 533, check with Delta Air Lines.

DL 533 earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 8 points better than the national rate of 77.6%. When something does go wrong the average delay runs a little over an hour. That rests on 316 flights, with a median arrival 9 minutes early.

Set against the rest of the country, DL 533's record is 8 points better than the US average of 77.6%. That gap is worth roughly 79 fewer late arrivals for every thousand flights.

On time

85.5%

Arrivals under 15 minutes late, of 311 completed flights

Avg delay

72 min

Across delayed arrivals only, not all flights

Cancelled

0.95%

National rate is 1.81%

1 hour+ late

3.5%

National rate is 8.1%

These figures cover 316 flights between July 2025 and June 2026. The median arrival is 9 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 533 flies

DL 533 flies SEA to DTW without a single fixed slot. Its most common scheduled departure was 15:15, used on 99 of 316 flights, with 13:30 (89 flights) and 15:40 (60 flights) next. Carriers retime flights through the season, so the rates here blend slightly different positions in the aircraft's day.

Departs 15:1599 flights31.3%
Departs 13:3089 flights28.2%
Departs 15:4060 flights19.0%

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 15:15 departure sits in the 2pm–5pm window. Across every US flight scheduled in that window the on-time rate is 72.4%, and DL 533 runs 13 points better at 85.5%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.

Against the route

DL 533 next to SEA to DTW

Every carrier on SEA to DTW combined arrived on time 84.7% of the time across 2,072 flights, so DL 533 is about level with it. Delta flew 1,532 flights on the same city pair under all its flight numbers, including this one, and those ran 85.3% on time. Across its whole network Delta Air Lines managed 81.6%, which this flight beats by 4 points.

DL 533 against its route and carrier
Compared with	Flights	On time	Avg delay	Cancelled	Grade
DL 533thin sample	316	85.5%	72 min	0.95%	A+
All Delta Air Lines on SEA–DTW	1,532	85.3%	65 min	1.04%	A
All carriers on SEA–DTW	2,072	84.7%	59 min	0.82%	B+
Delta Air Lines, whole network	1,038,570	81.6%	71 min	1.62%	B

Across the year

DL 533 quarter by quarter

DL 533 did not run the same all year. Its best quarter was Oct–Dec 2025 at 93.7% on time and its weakest Jan–Mar 2026 at 75.3%, a swing of 18 points on roughly 79 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 202578 flights79.2%
Oct–Dec 202579 flights93.7%
Jan–Mar 202679 flights75.3%
Apr–Jun 202680 flights93.6%

Scale runs 65% to 100%. Rows with fewer than 30 flights show a dash.

By weekday, DL 533 ranged from 80.0% on Sunday to 91.5% on Wednesday. With about 45 flights behind each day, a spread of 12 points is inside normal variation, so the day you fly is not worth changing for this flight.

Delay causes

Why DL 533 runs late

One category carries most of the weight here. Carrier accounts for 59% of the 3,221 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
59%
Late-arriving aircraft
27%
National Airspace System
13%
Extreme weather
1%

The largest share of delay minutes, 59%, 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 1,896 of the 3,221 delay minutes reported here. The split is drawn from 3,221 delay minutes reported on DL 533.

Cancellations sit at 0.95% against a national 1.81%, which is ordinary. Diversions add another 0.63%.

Connections and routes

What a delay on this flight costs

Badly late arrivals are rare here: only 3.5% 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.

At 1,927 miles this is transcontinental flying, and long routes get a quiet structural advantage. Scheduled block time on a flight this length carries more padding in absolute minutes, so a twenty-minute late departure often still becomes an on-time arrival. Read the on-time rate here as slightly flattering next to a short-haul route with the same operational quality.

The same number turns up on two other city pairs in the data, including PHL to ATL (16) and ATL to PHL (16), but none flew often enough under DL 533 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SEA to DTW only.

One caution: this is a thin sample. 316 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 533

For a booking, DL 533 has one of the better records a US domestic flight can show: 85.5% on time and 0.95% 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