Route reliability record
ATL→SFO
Atlanta to San Francisco
- Flights
- 3,339
- Period
- September 2025 to August 2026
- Distance
- 2,139 mi
- Carriers
- 3
This route sits in the middle of the pack with a C+. About seven flights in ten arrive on time by the DOT's definition, 7 points worse than the national rate of 77.3%. The late ones land about an hour behind schedule. That rests on 3,339 ATL to SFO flights, of which United Airlines flew 636 at 76.9% on time.
Best time to fly ATL to SFO: a 5am–8am departure, ideally on a Tuesday. Flights in that window arrived on time 85.1% of the time and Tuesday flights 78.2%, against 69.9% for the route overall.
The national on-time rate over the same period is 77.3%, so this route runs 7 points behind the country as a whole. Across a thousand flights that is about 74 extra late arrivals.
Key figures
On time
69.9%
Arrivals under 15 minutes late, of 3,309 completed flights
Avg delay
58 min
Across delayed arrivals only, not all flights
Cancelled
0.69%
National rate is 1.89%
Best carrier
United
76.9% on time across 636 flights
These figures cover 3,339 flights between September 2025 and August 2026. Beyond the headline rate, 9.3% of arrivals land a full hour or more behind schedule, against 8.3% nationally.
Fare search by Aviasales, a Travelpayouts partner. Booking through it may earn this site a commission at no cost to you; it changes no figure here.
Carrier by carrier
Which airline is most reliable on ATL to SFO
The choice of carrier is not cosmetic here. United Airlines arrives on time 76.9% of the time; Delta Air Lines manages 68.5%. Sample sizes sit next to every figure, because a two-point gap across 2,393 flights means less than a ten-point one.
| Airline | Flights | On time | Avg delay | Cancelled | Grade |
|---|---|---|---|---|---|
| United Airlines | 636 | 76.9% | 69 min | 0.47% | B+ |
| Delta Air Lines | 2,393 | 68.5% | 55 min | 0.67% | C+ |
| Frontier Airlinesthin sample | 310 | 65.6% | 63 min | 1.29% | C |
United leads Delta by 8 points. Real, but small enough that a better departure time on the weaker carrier can outweigh it.
Flight by flight
Flights on ATL to SFO
The flight numbers below flew this route at least 250 times in the period, busiest first. Each has its own record, with its schedule and delay causes.
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.
Best ways to make this trip
The most reliable ways to fly Atlanta to San Francisco
Every airline on this route and on the routes between nearby airports, ranked by how often a scheduled flight actually operated and arrived on time. 1 of the top 3 use a different airport at one end.
| Option | Airline | Success | On time | Cancelled | Best departure | Most punctual flight |
|---|---|---|---|---|---|---|
| 1. ATL → SJCAtlanta to San Jose | Delta Air Lines | 84.8% | 85.8% | 1.22% | 8am–11am, Tue | DL 809 09:40 |
| 2. ATL → SFOAtlanta to San Francisco | United Airlines | 76.5% | 76.9% | 0.47% | 5am–8am, Wed | — |
| 3. ATL → SFOAtlanta to San Francisco | Delta Air Lines | 68.0% | 68.5% | 0.67% | 8am–11am, Tue | DL 693 08:25 |
Success is the share of scheduled flights that operated and arrived less than 15 minutes late, so a cancelled flight counts against it. “(route)” means the best time comes from every carrier on the route rather than this airline alone.
Departure window
The best time of day to leave
Departure time matters more here than the choice of carrier. The gap between the best and worst window is 22 points, against 8 points between the best and worst carrier.
- 5am–8am344 flights85.1%
- 8am–11am791 flights74.9%
- 11am–2pm210 flights69.4%
- 2pm–5pm430 flights69.3%
- 5pm–8pm1,030 flights63.2%
- 8pm–5am534 flights66.0%
Scale runs 55% to 90%.
The 5pm–8pm window is where this operation falls apart: 63.2% on time, against 85.1% for the 5am–8am slot. By evening the aircraft flying these rotations have absorbed a full day of small delays and there is no slack left to recover in. The 5pm–8pm window is the busiest, with 1,030 flights scheduled in it.
Explore
Filter ATL to SFO by airline, time, month and day
Pick a breakdown and a carrier. The dashed mark on each row is the same slice for every US flight.
On ATL to SFO, the best departure window is 5am–8am at 85.1% on time and the worst is 5pm–8pm at 63.2%, a wide gap of 21.9 points. All US flights leaving 5am–8am ran 89.3%.
- 5–8am85.1%
- 8–11am74.9%
- 11am–2pm69.4%
- 2–5pm69.3%
- 5–8pm63.2%
- 8pm–5am66.0%
best all US flightsScale 55% to 95%.
Across the year
When delays peak on this route
This route's year swings by 31 points from best month to worst, which is wide. An annual average tells you very little about the week you are actually flying, so read the strip rather than the headline if your dates are fixed.
July is the worst month at 55.7% on time, 31 points below March, the best at 86.6%. 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. July was the busiest month here, with 317 flights.
Across the week, Tuesday is the strongest day at 78.2% on time and Sunday the weakest at 61.5%, a spread of 17 points.
Delay causes
Why this route gets delayed
National Airspace System accounts for 46% of the 57,000 delay minutes carriers reported here, and the remaining four split what is left.
- 46%National Airspace System
- 36%Carrier
- 15%Late-arriving aircraft
- 3%Extreme weather
The largest share of delay minutes, 36%, falls under carrier control: crew scheduling, maintenance, fuelling, baggage. It accounts for 21,000 of the 57,000 delay minutes reported here. The split is drawn from 57,429 reported delay minutes.
46% of delay minutes are charged to the National Airspace System: air traffic volume, runway configuration, ground stops. No carrier can price its way out of that, which is why airport choice moves the number here more than carrier choice does. That is 27,000 minutes out of 57,000, against a national NAS share of 21%.
Cancellations are rare at 0.69%, 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 actually costs
9.3% of arrivals land a full hour or more behind schedule, against 8.3% nationally. Ninety minutes is the honest minimum for a connection here, and two hours if the onward flight is on a separate ticket.
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 80.2% on time across 3,337 flights, 10 points above 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 10 points of difference.
The sample behind these figures is 3,339 flights, enough that the headline rate is stable to within roughly a point. The hour-block and month splits divide that further, so read the thinner bars with more caution than the headline.
Work out the risk of missing a connection in SFO after this flight
What to do with this
Booking this route
Put together: the calendar is the biggest lever here, not the carrier or the hour. March runs 86.6% on time and July 55.7%, a swing of 31 points. If the dates move at all, move them out of July before you think about anything else. 3,309 completed flights over 12 months sit behind that.
Common questions
ATL to SFO questions
How often is ATL to SFO delayed?
Roughly one flight in three arrives at least 15 minutes late, which is the Department of Transportation's definition of a delayed arrival. That works out to 30.1% of the 3,339 flights in this analysis, against 22.7% nationally. Delayed flights are late by about an hour on average.
Which airline is most reliable on ATL to SFO?
United Airlines leads at 76.9% on time across 636 flights. Delta Air Lines is at the other end on 68.5%, a gap of 8 points. Sample size matters as much as the percentage: a rate built from a few hundred flights moves around far more than one built from ten thousand.
What time of day has the fewest delays on ATL to SFO?
The 5am–8am departure window is the strongest at 85.1% on time. The 5pm–8pm window is the weakest at 63.2%, 22 points behind. Later departures inherit delays from earlier flights the same aircraft has already flown, which is why the curve slopes the way it does.
How bad are July delays on ATL to SFO?
July is the weakest month at 55.7% on time, compared with 86.6% in March. Across the year that is 31 points between the best and worst months. Moving flexible dates out of that month is one of the few things that reliably helps.
Related
Where to go next
- SFO to ATL — the return legseparate record
- Hartsfield-Jackson Atlanta International (ATL) delay statistics
- San Francisco International (SFO) delay statistics
- United Airlines on ATL to SFO76.9%
- Delta Air Lines on ATL to SFO68.5%
- Frontier Airlines on ATL to SFO65.6%
- ATL to LGA, a related route72.3%
- LAX to SFO, a related route60.1%
- ATL to MCO, a related route70.3%
- United Airlines on-time record76.9%
- Delta Air Lines on-time record68.5%
- Frontier Airlines on-time record65.6%
- The best time of day to fly, according to 7.05 million flight records
- How often a connection fails at the major US hubs
Direction matters. ATL to SFO and SFO to ATL are scored separately because they are separate operations, with different departure banks and different aircraft. Compare the return leg.
Embed ATL to SFO’s on-time badge on your site
Paste this into a web page. The badge shows the current on-time rate, cancellation rate and grade, and updates every month. Preview it, or build a badge for another route or airport.
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.