Carrier route record
UASFO→BNA
United Airlines · San Francisco to Nashville
- Flights
- 851
- Period
- July 2025 to June 2026
- Share of route
- 73%
- Carriers
- 2
Historical statistics for July 2025 to June 2026, not live status. For today’s flights, check with United Airlines.
United on SFO to BNA lands a B+, 2 points better than the national rate of 77.6%. About one flight in five arrives 15 minutes late or worse, and those flights are late by roughly 55 minutes on average. That is a workable record, not a spotless one. That rests on 851 flights, with a median arrival 4 minutes early.
The US average over the same twelve months is 77.6%, so there is little to separate United on SFO to BNA from the country as a whole. The variation that matters here is internal: which carrier, and what time of day.
Key figures
On time
79.9%
Arrivals under 15 minutes late, of 845 completed flights
Avg delay
53 min
Across delayed arrivals only, not all flights
Cancelled
0.71%
National rate is 1.81%
Whole route
73.9%
Every carrier on SFO to BNA, 1,162 flights
These figures cover 851 flights between July 2025 and June 2026. The median arrival is 4 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
United against every carrier on SFO to BNA
United flew 851 of the 1,162 flights on SFO to BNA, most of the route. Its 79.9% on time is 6 points better than the route as a whole, which runs 73.9%. Ranked by on-time rate it is first of two carriers on the route, where the range runs from United at 79.9% to Southwest at 57.6%. 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 |
|---|---|---|---|---|---|
| United Airlines (this page) | 851 | 79.9% | 53 min | 0.71% | B+ |
| Southwest Airlinesthin sample | 311 | 57.6% | 50 min | 0.32% | D+ |
Flight by flight
United flight numbers on SFO to BNA
Departure window
When United runs best on this route
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 16 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–8am—
- 8am–11am322 flights82.6%
- 11am–2pm57 flights89.1%
- 2pm–5pm186 flights73.2%
- 5pm–8pm25 flights—
- 8pm–5am261 flights79.6%
Scale runs 65% to 95%. Rows with fewer than 30 flights show a dash.
The best window here is not the first bank but the 11am–2pm slot at 89.1% on time, ahead of 2pm–5pm at 73.2%. Where the curve peaks mid-day rather than at dawn, the constraint is usually congestion at one end rather than the aircraft's own rotation. The 8am–11am window is the busiest, with 322 flights scheduled in it.
Across the year
United on SFO to BNA through the year
June is the worst month at 71.4% on time, 17 points below September, the best at 88.7%. 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. March was the busiest month here, with 83 flights.
Across the week, Tuesday is the strongest day at 85.3% on time and Sunday the weakest at 73.3%. 12 points is a smaller lever than departure hour, but it is free.
Delay causes
Why United runs late on this route
One category carries most of the weight here. Late-arriving aircraft accounts for 49% of the 9,047 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.
- 49%Late-arriving aircraft
- 31%Carrier
- 20%National Airspace System
49% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. That is a cascade, and cascades start small and grow through the day. Across 9,047 reported delay minutes here, that single category outweighs weather by 49 to one. It is the strongest argument for booking the first departure of the morning, when the aircraft has been sitting at the gate overnight with nothing to inherit. The split is drawn from 9,047 reported delay minutes.
Cancellations are rare at 0.71%, 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
5.0% of arrivals land an hour or more late, close to the national 8.1%. That is the figure that decides a connection, and it says a 60 to 75 minute layover is reasonable here while anything under 45 minutes is a bet. Most delays on this route last roughly 55 minutes, which a normal layover absorbs.
At 1,969 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 is a different operation and performs like one: it runs 76.3% on time across 851 flights, 4 points below this direction. Departure banks, aircraft rotations and the congestion at each end all differ, so scoring the two directions together would average away a real 4 points of difference.
One caution: this is a thin sample. 851 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 United on SFO to BNA
Put together: treat all of this as provisional. 851 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 79.9% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 845 completed flights over 12 months sit behind that.
Related
Where to go next
- SFO to BNA, every carrier
- United on BNA to SFO, the return leg
- Southwest Airlines on SFO to BNA57.6%
- United Airlines network-wide record
- San Francisco International (SFO) delay statistics
- Nashville International (BNA) delay statistics
- Why the first flight of the morning is statistically safest
- The best time of day to fly, according to 7.04 million flight records
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.