Carrier route record
DLBNA→SEA
Delta Air Lines · Nashville to Seattle
- Flights
- 511
- Period
- July 2025 to June 2026
- Share of route
- 35%
- Carriers
- 3
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with Delta Air Lines.
Delta on BNA to SEA lands a B+, 6 points better than the national rate of 77.6%. About one flight in six arrives 15 minutes late or worse, and those flights are late by about an hour on average. That is a workable record, not a spotless one. That rests on 511 flights, with a median arrival 7 minutes early.
Set against the rest of the country, Delta's BNA to SEA record is 6 points better than the US average of 77.6%. That gap is worth roughly 58 fewer late arrivals for every thousand flights.
Key figures
On time
83.4%
Arrivals under 15 minutes late, of 507 completed flights
Avg delay
66 min
Across delayed arrivals only, not all flights
Cancelled
0.78%
National rate is 1.81%
Whole route
72.7%
Every carrier on BNA to SEA, 1,479 flights
These figures cover 511 flights between July 2025 and June 2026. The median arrival is 7 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 BNA to SEA
Delta flew 511 of the 1,479 flights on BNA to SEA, about 35% of it. Its 83.4% on time is 11 points better than the route as a whole, which runs 72.7%. Ranked by on-time rate it is first of three carriers on the route, where the range runs from Delta at 83.4% to Southwest at 44.7%. One of those carriers flew fewer than 365 flights here, so treat their positions as rough.
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.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| Delta Air Lines (this page) | 511 | 83.4% | 66 min | 0.78% | B+ |
| Alaska Airlines | 843 | 70.3% | 49 min | 1.42% | C |
| Southwest Airlinesthin sample | 125 | 44.7% | 52 min | 0.80% | F+ |
Flight by flight
Delta flight numbers on BNA to SEA
Departure window
When Delta runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 11 points, against half a point between the best and worst carrier. Each bar is the on-time rate for flights scheduled inside that window.
- 5am–8am364 flights85.6%
- 8am–11am—
- 11am–2pm—
- 2pm–5pm31 flights74.2%
- 5pm–8pm116 flights79.1%
- 8pm–5am—
Scale runs 65% to 90%. Rows with fewer than 30 flights show a dash.
Book the early departure. Flights leaving between 5am–8am arrive on time 85.6% of the time, against 74.2% for the afternoon window. That is 11 points of difference for no extra money, and it comes from the same aircraft having had no earlier flight to fall behind on. The 5am–8am window is the busiest, with 364 flights scheduled in it.
Across the year
Delta on BNA to SEA through the year
December is the weak month at 74.2% on time, against 93.8% in September. Winter delays cluster: a single storm system can account for most of a month's shortfall, so an average December hides both very good weeks and genuinely unflyable days. May was the busiest month here, with 61 flights.
Across the week, Wednesday is the strongest day at 91.7% on time and Sunday the weakest at 79.2%. 13 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 54% of the 5,574 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.
- 54%Carrier
- 23%National Airspace System
- 20%Late-arriving aircraft
- 3%Extreme weather
The largest share of delay minutes, 54%, 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 3,010 of the 5,574 delay minutes reported here. The split is drawn from 5,574 reported delay minutes.
Cancellations are rare at 0.78%, 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 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.
At 1,978 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 84.6% on time across 511 flights, within about a point 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. 511 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 BNA to SEA
Put together: treat all of this as provisional. 511 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 83.4% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 507 completed flights over 12 months sit behind that.
Related
Where to go next
- BNA to SEA, every carrier
- Delta on SEA to BNA, the return leg
- Alaska Airlines on BNA to SEA70.3%
- Southwest Airlines on BNA to SEA44.7%
- Delta Air Lines network-wide record
- Nashville International (BNA) delay statistics
- Seattle-Tacoma International (SEA) delay statistics
- The best time of day to fly, according to 7.04 million flight records
- Worst months to fly in the US, ranked by the data
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.