Flight number record
DL 558
Delta Air Lines · Seattle to Cincinnati
- Route
- SEA → CVG
- Departs
- 11:45
- Flights
- 346
- Period
- September 2025 to August 2026
Historical statistics for September 2025 to August 2026, not live status. For today’s DL 558, check with Delta Air Lines.
DL 558 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 12 points better than the national rate of 77.3%. When something does go wrong the average delay runs about an hour. That rests on 346 flights, with a median arrival 14 minutes early.
Set against the rest of the country, DL 558's record is 12 points better than the US average of 77.3%. That gap is worth roughly 122 fewer late arrivals for every thousand flights.
Key figures
On time
89.5%
Arrivals under 15 minutes late, of 342 completed flights
Avg delay
60 min
Across delayed arrivals only, not all flights
Cancelled
0.87%
National rate is 1.89%
1 hour+ late
3.8%
National rate is 8.3%
These figures cover 346 flights between September 2025 and August 2026. The median arrival is 14 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.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Schedule
When DL 558 flies
DL 558 flies SEA to CVG without a single fixed slot. Its most common scheduled departure was 11:45, used on 178 of 346 flights, with 11:25 (67 flights) and 11:40 (41 flights) next.
- Departs 11:45178 flights51.4%
- Departs 11:2567 flights19.4%
- Departs 11:4041 flights11.8%
Scale runs 0% to 100%.
Share of scheduled departures at each local time. Times used on fewer than one flight in ten are not listed.
A 11:45 departure sits in the 11am–2pm window. Across every US flight scheduled in that window the on-time rate is 78.3%, and DL 558 runs 11 points better at 89.5%. Midday slots inherit some of the morning's delays without yet carrying the full weight of the evening's.
Timetable by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Against the route
DL 558 next to SEA to CVG
Every carrier on SEA to CVG combined arrived on time 86.2% of the time across 793 flights, so DL 558 is 3 points ahead of it. Across its whole network Delta Air Lines managed 81.1%, which this flight beats by 8 points.
| Compared with | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| DL 558thin sample | 346 | 89.5% | 60 min | 0.87% | A+ |
| All Delta Air Lines on SEA–CVGthin sample | 362 | 89.6% | 59 min | 1.10% | A |
| All carriers on SEA–CVG | 793 | 86.2% | 46 min | 1.13% | A |
| Delta Air Lines, whole network | 1,039,517 | 81.1% | 71 min | 1.74% | B |
Across the year
DL 558 quarter by quarter
DL 558 did not run the same all year. Its best quarter was Jul–Sep 2025 at 96.7% on time and its weakest Jan–Mar 2026 at 83.3%, a swing of 13 points on roughly 69 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 202530 flights96.7%
- Oct–Dec 202577 flights94.8%
- Jan–Mar 202686 flights83.3%
- Apr–Jun 202691 flights86.7%
- Jul–Sep 202662 flights91.8%
Scale runs 75% to 100%.
By weekday, DL 558 ranged from 85.4% on Sunday to 95.7% on Friday. With about 49 flights behind each day, a spread of 10 points is inside normal variation, so the day you fly is not worth changing for this flight.
Arrival by arrival
How late DL 558 runs when it is late
DL 558 often beats the schedule: 162 of 342 completed flights, 47%, arrived 15 minutes or more early. The 36 late arrivals split 16 under half an hour, 7 between 30 and 60 minutes, and 13 an hour or more.
- 15+ min early162 flights47.4%
- Within 15 min144 flights42.1%
- 15–29 min late16 flights4.7%
- 30–59 min late7 flights2.0%
- 1–2 hours late9 flights2.6%
- 2+ hours late4 flights1.2%
Scale runs 0% to 100%.
Share of 342 completed flights by arrival against schedule.
7 of 34 late departures made up the time and arrived on time, 21% of them. 9 flights left on time and still arrived late.
The worst days
Worst days for DL 558
The latest arrival of the period was on 9 November 2025, 3 hours 32 minutes behind schedule; most of its delay minutes were filed as a late-arriving aircraft. On three of the five worst days the largest share was filed as carrier-caused (crew, maintenance, fuelling, baggage).
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 9 November 2025 | 3 hours 32 minutes | Late-arriving aircraft |
| 26 April 2026 | 3 hours 7 minutes | Carrier |
| 13 February 2026 | 2 hours 47 minutes | Carrier |
| 7 January 2026 | 2 hours 4 minutes | Carrier |
| 12 January 2026 | 1 hour 44 minutes | Late-arriving aircraft |
Delay causes
Why DL 558 runs late
Carrier accounts for 57% of the 2,147 delay minutes carriers reported here, and the remaining four split what is left.
- 57%Carrier
- 27%Late-arriving aircraft
- 14%National Airspace System
- 3%Extreme weather
The largest share of delay minutes, 57%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 1,215 of the 2,147 delay minutes reported here. The split is drawn from 2,147 delay minutes reported on DL 558.
Cancellations are rare at 0.87%, below the national 1.89% 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 3.8% land an hour or more behind schedule, against 8.3% 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 1,965 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 one other city pair in the data, including CVG to SEA (16), but none flew often enough under DL 558 to report a rate for. Carriers move flight numbers between routes, so the figures on this page apply to SEA to CVG only.
One caution: this is a thin sample. 346 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 558
For a booking, DL 558 has one of the better records a US domestic flight can show: 89.5% on time and 0.87% cancelled. That is a base rate, not a promise about any single day.
Related
Where to go next
- SEA to CVG, every carrier and departure
- CVG to SEA, the return direction
- Alaska Airlines 508 on the same route83.6%
- Seattle-Tacoma International (SEA) delay statistics
- Cincinnati/Northern Kentucky International (CVG) delay statistics
- Delta Air Lines on-time record
- Every Delta Air Lines flight number with a record
- The most and least reliable flight numbers in the US
- Worst months to fly in the US, ranked by the data
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, September 2025 to August 2026. Last updated ; recomputed monthly. How this data is collected.