Carrier route record

DLSEA→CVG

Delta Air Lines · Seattle to Cincinnati

Flights: 362
Period: July 2025 to June 2026
Share of route: 46%
Carriers: 2

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

Delta on SEA to CVG 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 10 points better than the national rate of 77.6%. When something does go wrong the average delay runs about an hour. That rests on 362 flights, with a median arrival 13 minutes early.

Set against the rest of the country, Delta's SEA to CVG record is 10 points better than the US average of 77.6%. That gap is worth roughly 95 fewer late arrivals for every thousand flights.

On time

87.1%

Arrivals under 15 minutes late, of 356 completed flights

Avg delay

62 min

Across delayed arrivals only, not all flights

Cancelled

0.83%

National rate is 1.81%

Whole route

81.7%

Every carrier on SEA to CVG, 793 flights

These figures cover 362 flights between July 2025 and June 2026. The median arrival is 13 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.

Carrier by carrier

Delta against every carrier on SEA to CVG

Delta flew 362 of the 793 flights on SEA to CVG, about 46% of it. Its 87.1% on time is 5 points better than the route as a whole, which runs 81.7%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from Delta at 87.1% to Alaska at 77.2%.

Only one carrier clears this site's 365-flight floor here, so there is no comparison to draw. The table below is the full picture.

On-time performance by carrier on SEA to CVG
Airline	Flights	On time	Avg delay	Cancelled	Grade
Delta Air Lines (this page)thin sample	362	87.1%	62 min	0.83%	A+
Alaska Airlines	431	77.2%	46 min	0.93%	B+

Flight by flight

Delta flight numbers on SEA to CVG

DL 55811:4586.8% · 346 flights

Departure window

When Delta runs best on this route

Departure time is the single lever a traveller controls, and it moves the odds more than most people expect. Each bar below is the on-time rate for flights scheduled to leave inside that window, across 362 flights.

There are not enough flights in each departure window to split Delta's SEA to CVG record by time of day without the percentages moving on noise. The headline rate of 87.1% is the reliable figure here.

Across the year

Delta on SEA to CVG through the year

Darker means more delays. Figures are on-time percentages.September best, July worst

July is the worst month at 70.0% on time, 27 points below September, the best at 96.7%. Summer afternoon convection and peak-season schedules land on the same weeks every year, so this is a pattern you can book around rather than a run of bad luck. January was the busiest month here, with 31 flights.

Across the week, Friday is the strongest day at 95.9% on time and Tuesday the weakest at 81.1%. 15 points is a smaller lever than departure hour, but it is free.

Delay causes

Why Delta runs late on this route

One category carries most of the weight here. Carrier accounts for 57% of the 2,833 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
57%
Late-arriving aircraft
25%
National Airspace System
18%

The largest share of delay minutes, 57%, 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 1,608 of the 2,833 delay minutes reported here. The split is drawn from 2,833 reported delay minutes.

Cancellations are rare at 0.83%, 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 stage length

What a delay here costs

Badly late arrivals are rare here: only 4.2% 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.

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 return leg runs 84.7% on time across 362 flights, within 2 points of this direction. The two legs are scored separately because they usually differ; on this city pair they happen not to.

One caution: this is a thin sample. 362 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 Delta on SEA to CVG

Put together: treat all of this as provisional. 362 flights over twelve months is enough to clear this site's floor and not enough to be confident to better than a couple of points. The 87.1% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 356 completed flights over 12 months sit behind that.

Where to go next

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