Route profile
BNA→SEA
Flight reliability, delays and best times to fly from Nashville to Seattle, 1,978 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 70% of comparable major US routes (4,598 compared)
Calculated from 4,287 flights. How this is calculated
BNA → SEA arrives on time 78.3% of the time; the return trip, SEA → BNA, arrives on time 78.1% of the time.
BNA → SEA spends 31.3 minutes on the ground on a 1,978-mile trip: 18.6 minutes from pushback to wheels-up at BNA and 12.7 minutes from touchdown to gate at SEA.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What stands out
The airline matters unusually much on this route, a wider carrier-to-carrier gap than 100% of 2,692 comparable routes.
Delta Air Lines arrived on time 86.0% of the time, against 51.0% for Southwest Airlines, flying the exact same route.
Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · Ranked against every other route with the same kind of figure and at least 2,692 in the comparison.
What sets this route apart
Where BNA to SEA differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
BNA to SEA struggles most at 6 PM: 61.4% of its flights scheduled then arrive on time, 8.5 points behind the 69.9% on routes of similar length at the same hour. Against all other routes the gap is 7.2 points.
BNA to SEA is at its best against routes of similar length for flights scheduled at 4 PM: 80.3% arrive on time, 7.2 points ahead of the 73.1% those routes manage at that hour. Against all other routes the gap is 9.6 points.
Thursday is the day BNA to SEA slips furthest against routes of similar length, 73.6% on time where they average 77.5%, 3.9 points lower.
In December, BNA to SEA runs 7.8 points below routes of similar length, 72.5% on time to 80.3%. Against all other routes the gap is 6.3 points.
Delta Air Lines does better on BNA to SEA than on its routes of similar length: 86.0% on time here, 81.6% there, 4.4 points apart. Against all other routes the gap is 4.5 points.
BNA to SEA against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 6 PM departures | 61.4% | routes of similar length | 69.9% | −8.5 pts | 277 here, 54,242 there |
| Hour: 4 PM departures | 80.3% | routes of similar length | 73.1% | +7.2 pts | 173 here, 57,102 there |
| Weekday: Thursday | 73.6% | routes of similar length | 77.5% | −3.9 pts | 611 here, 158,453 there |
| Month: December | 72.5% | routes of similar length | 80.3% | −7.8 pts | 273 here, 84,782 there |
| Airline: Delta Air Lines | 86.0% | routes of similar length | 81.6% | +4.4 pts | 1,316 here, 287,742 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 1,978 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
When it goes wrong
July 2023 – July 2026
35 min late
against a median of 5 min early
Percentiles over 4,287 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at SEA after arriving from BNA.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 39% | Likely to miss |
| 45 min | 21% | High risk |
| 60 min | 11% | Some risk |
| 90 min | 4.4% | Low risk |
| 120 min | 2.4% | Low risk |
This is one leg of a connection. Gate changes and the next flight's own schedule matter too. And a connection can fail before delay is even the question — this route cancels 0.91% of the time and diverts 0.14% of the time, which a late arrival never shows up in.
Chance of missing is the share of 4,242 arrivals on this route that landed later than the connection time less 30 minutes to reach the next gate.
The worst tenth of arrivals on this route land at least 35 minutes late (90th-percentile gate arrival delay), over 4,287 operations.
Any other layover length: connection checker.
Best time to fly
BNA → SEA flights departing 9 AM–12 PM arrived on time 88.2% of the time, against 59.8% for 6–9 PM departures, a gap of 28.4 percentage points.
By departure window
By departure hour
- 12 AM to 6 AM: too few flights to score
- 7 AM: 83.1% on time from 2,176 flights
- 8 AM: too few flights to score
- 9 AM: 88.2% on time from 594 flights
- 10 AM to 3 PM: too few flights to score
- 4 PM: 80.3% on time from 175 flights
- 5 PM: 69.1% on time from 793 flights
- 6 PM: 61.4% on time from 280 flights
- 7 PM to 11 PM: too few flights to score
Departure windows with fewer than 120 flights are not scored.
Why BNA → SEA runs late
July 2023 – July 2026
crew, maintenance, boarding and fueling, all within the carrier’s control
the inbound aircraft was late, so this flight started late
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for BNA → SEA. Only delays of 15 minutes or more are attributed.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| Alaska Airlines | 2,750 | 76.7% | 1.09% | -3 min | 4.5% |
| Delta Air Lines | 1,325 | 86.0% | 0.60% | -11 min | 3.5% |
| Southwest Airlines | 212 | 51.0% | 0.47% | 13 min | 13.3% |
Alaska Airlines flew 64.1% of the 4,287 flights listed.
Delta Air Lines arrived on time 35.0 percentage points more often than Southwest Airlines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| DL372 Delta Air Lines | 7:00 AM | 1,124 | 88.2% |
Weekly and seasonal patterns
By day of week
Wednesday is historically the most reliable day and Thursday the least, a gap of 10.4 percentage points.
By month
- Jan: 77.9%
- Feb: 83.0%
- Mar: 81.7%
- Apr: 82.2%
- May: 79.0%
- Jun: 71.9%
- Jul: 71.2%
- Aug: 77.2%
- Sep: 82.1%
- Oct: 86.7%
- Nov: 84.2%
- Dec: 72.5%
July is historically the weakest month and October the strongest, a spread of 15.5 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: too few flights to score (118)
- August 2023: 91.5% from 120 flights
- September 2023: too few flights to score (116)
- October 2023: too few flights to score (119)
- November 2023: too few flights to score (102)
- December 2023: too few flights to score (93)
- January 2024: too few flights to score (90)
- February 2024: too few flights to score (83)
- March 2024: too few flights to score (105)
- April 2024: too few flights to score (116)
- May 2024: 71.3% from 122 flights
- June 2024: 75.2% from 125 flights
- July 2024: 84.3% from 128 flights
- August 2024: 82.4% from 126 flights
- September 2024: 84.8% from 125 flights
- October 2024: too few flights to score (113)
- November 2024: too few flights to score (88)
- December 2024: too few flights to score (91)
- January 2025: too few flights to score (82)
- February 2025: too few flights to score (76)
- March 2025: too few flights to score (90)
- April 2025: too few flights to score (98)
- May 2025: 86.1% from 124 flights
- June 2025: 71.5% from 173 flights
- July 2025: 72.0% from 188 flights
- August 2025: 63.8% from 176 flights
- September 2025: 74.8% from 135 flights
- October 2025: too few flights to score (117)
- November 2025: too few flights to score (88)
- December 2025: too few flights to score (90)
- January 2026: too few flights to score (81)
- February 2026: too few flights to score (76)
- March 2026: too few flights to score (91)
- April 2026: too few flights to score (118)
- May 2026: 79.4% from 142 flights
- June 2026: 69.9% from 177 flights
- July 2026: 63.9% from 185 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 71.7% against 80.1% in the 12 months before — declining by 8.4 percentage points.
Data and methodology
Calculated by FlyerIntel from 4,287 BNA → SEA flight records from the US DOT Bureau of Transportation Statistics, covering July 2023 – July 2026. Late means 15 or more minutes past scheduled arrival; cancelled and diverted flights are left out of on-time rates.
Full methodology · Data sources · Report a problem
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed