Carrier route record
UASFO→ATL
United Airlines · San Francisco to Atlanta
- Flights
- 636
- Period
- September 2025 to August 2026
- Share of route
- 19%
- Carriers
- 3
Historical statistics for September 2025 to August 2026, not live status. For today’s flights, check with United Airlines.
United on SFO to ATL earns an A+. More than four flights in five arrive inside the 15-minute window the DOT uses to define an on-time arrival, which puts it 9 points better than the national rate of 77.3%. When something does go wrong the average delay runs about 50 minutes. That rests on 636 flights, with a median arrival 8 minutes early.
Set against the rest of the country, United's SFO to ATL record is 9 points better than the US average of 77.3%. That gap is worth roughly 86 fewer late arrivals for every thousand flights.
Key figures
On time
85.9%
Arrivals under 15 minutes late, of 632 completed flights
Avg delay
50 min
Across delayed arrivals only, not all flights
Cancelled
0.16%
National rate is 1.89%
Whole route
80.2%
Every carrier on SFO to ATL, 3,337 flights
These figures cover 636 flights between September 2025 and August 2026. The median arrival is 8 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.
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Carrier by carrier
United against every carrier on SFO to ATL
United flew 636 of the 3,337 flights on SFO to ATL, about 19% of it. Its 85.9% on time is 6 points better than the route as a whole, which runs 80.2%. Ranked by on-time rate it is first of three carriers on the route, where the range runs from United at 85.9% to Frontier at 61.2%. 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) | 636 | 85.9% | 50 min | 0.16% | A+ |
| Delta Air Lines | 2,390 | 81.1% | 70 min | 0.71% | B+ |
| Frontier Airlinesthin sample | 311 | 61.2% | 73 min | 3.54% | D− |
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.
Departure window
When United 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 636 flights.
- 5am–8am—
- 8am–11am359 flights87.2%
- 11am–2pm—
- 2pm–5pm8 flights—
- 5pm–8pm—
- 8pm–5am269 flights84.2%
Scale runs 75% to 95%. Rows with fewer than 30 flights show a dash.
The 8am–11am window is the strongest at 87.2% on time. The full set of windows spans 3 points.
Across the year
United on SFO to ATL through the year
July is the worst month at 72.1% on time, 22 points below October, the best at 94.5%. 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. November was the busiest month here, with 62 flights.
Across the week, Monday is the strongest day at 93.3% on time and Sunday the weakest at 80.0%, a spread of 13 points.
Arrival by arrival
How late United on SFO to ATL runs when it is late
United on SFO to ATL often beats the schedule: 207 of 632 completed flights, 33%, arrived 15 minutes or more early. The 89 late arrivals split 38 under half an hour, 30 between 30 and 60 minutes, and 21 an hour or more.
- 15+ min early207 flights32.8%
- Within 15 min336 flights53.2%
- 15–29 min late38 flights6.0%
- 30–59 min late30 flights4.7%
- 1–2 hours late14 flights2.2%
- 2+ hours late7 flights1.1%
Scale runs 0% to 100%.
Share of 632 completed flights by arrival against schedule.
A late pushback is often recovered here: of 113 departures that left 15 minutes late or more, 51 still arrived on time. 27 flights left on time and still arrived late.
The worst days
Worst days for United on SFO to ATL
The latest arrival of the period was on 31 March 2026, 3 hours 44 minutes behind schedule; most of its delay minutes were filed as carrier-caused (crew, maintenance, fuelling, baggage). The same cause led on three of the five worst days.
| Date | Arrived late by | Largest filed cause |
|---|---|---|
| 31 March 2026 | 3 hours 44 minutes | Carrier |
| 2 July 2026 | 3 hours 26 minutes | Carrier |
| 15 February 2026 | 3 hours 17 minutes | Late-arriving aircraft |
| 28 June 2026 | 3 hours 7 minutes | Late-arriving aircraft |
| 27 May 2026 | 2 hours 55 minutes | Carrier |
Delay causes
Why United runs late on this route
Late-arriving aircraft accounts for 43% of the 4,470 delay minutes carriers reported here, and the remaining four split what is left.
- 43%Late-arriving aircraft
- 39%Carrier
- 17%National Airspace System
- 1%Extreme weather
43% of delay minutes trace back to a late-arriving aircraft, meaning the plane was already behind before it got here. Across 4,470 reported delay minutes here, that single category outweighs weather by 29 to one. The split is drawn from 4,470 reported delay minutes.
The largest share of delay minutes, 39%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 1,759 of the 4,470 delay minutes reported here.
Cancellations are rare at 0.16%, 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 stage length
What a delay here costs
Badly late arrivals are rare here: only 3.3% 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 2,139 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 76.9% on time across 636 flights, 9 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 9 points of difference.
One caution: this is a thin sample. 636 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 ATL
Put together: treat all of this as provisional. 636 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 85.9% headline is the most reliable number on the page; the hour and month splits below it are built on a few dozen flights each. 632 completed flights over 12 months sit behind that.
Related
Where to go next
- SFO to ATL, every carrier
- United on ATL to SFO, the return leg
- Delta Air Lines on SFO to ATL81.1%
- Frontier Airlines on SFO to ATL61.2%
- United Airlines network-wide record
- San Francisco International (SFO) delay statistics
- Hartsfield-Jackson Atlanta International (ATL) delay statistics
- Why the first flight of the morning is statistically safest
- Worst months to fly in the US, ranked by the data
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.