Best time to fly out of San Francisco (SFO)

The early-flight folk wisdom holds up at San Francisco: departures in the 6–8am band left on time 93% of the time, against 69.5% in the 2–4pm band. These are historical odds, not forecasts. The records say what happened on this schedule over three years; they know nothing about tomorrow’s thunderstorm.

Data through June 2026 · Bureau of Transportation Statistics

On-time rate by hour and day

On this page, “on time” means a departure that pushed back less than 15 minutes behind its scheduled time — the Bureau of Transportation Statistics definition, and the one airlines are held to.

Share of departures that left on time, by hour band and day of week.
Departure time MonTueWedThuFriSatSun
Before 6am 89 90 93 91 88 89 92
6–8am 92 94 95 93 94 93 92
8–10am 85 89 89 87 86 87 86
10am–12pm 71 79 77 74 73 77 72
12–2pm 71 77 74 72 70 76 71
2–4pm 68 76 71 66 65 75 67
4–6pm 72 81 77 72 70 78 72
6–8pm 75 83 80 74 73 82 74
8–10pm 73 82 78 72 72 80 70
10pm–12am 75 83 79 73 73 79 71
fewer left on time more left on time

The steadiest stretch at SFO was 6–8am — 93% of departures left on time across 43,047 flights. The weakest was 2–4pm at 69.5%. 6–8am departures from SFO left on time 93% of the time across 43,047 flights; 6–8pm departures, 77% across 40,745. That is a gap of 16 points, and it is the whole case for the early flight.

The year at SFO

June was the hard month at SFO: 72.4% of departures left on time, across 36,293 flights. September was the easy one at 83.9%. Each month pools three years of that month, so a single bad week does not decide it.

Share of departures that left on time, by calendar month. Best month in green, worst in amber. The hairline sits at the overall rate, 78.7%.
Departure on-time share at SFO by calendar month
Month Share departures that left on time Flights
January 82.1% 32,085
February 77.4% 29,884
March 78.6% 34,952
April 77.2% 35,196
May 74.3% 36,973
June 72.4% 36,293
July 76.3% 36,987
August 80.2% 36,815
September 83.9% 35,140
October 83.1% 37,126
November 81.2% 35,379
December 77.5% 35,108

Airlines at SFO

Every airline with at least 100 departures from SFO, busiest first. These are that airline’s departures from this airport only — its record across the country sits on its own page.

Airline Left on time Typical delay Cancelled Departures
United Airlines 81.1% 63 min 0.8% 164,239
SkyWest Airlines 79.6% 72 min 1% 98,256
Delta Air Lines 79.5% 71 min 0.8% 39,922
American Airlines 78.7% 103 min 1.3% 33,607
Alaska Airlines 79.4% 58 min 1.4% 33,235
Southwest Airlines 62.8% 56 min 0.6% 25,086
JetBlue Airways 79.8% 81 min 0.9% 13,313
Frontier Airlines 63.2% 83 min 1.9% 12,139
Hawaiian Airlines 84% 73 min 3.6% 2,090

Hawaiian Airlines (through December 2025) stopped filing before June 2026. Its row covers a shorter run of months than the rest of the table, so its figure is not set against the others anywhere on this page.

What delays out of SFO were put down to

Airlines file a reason with every arrival running 15 minutes late or more. Across 86,930 flights that departed SFO and ran 15 minutes late or more, the delay minutes break down with 44.8% put down to late-arriving aircraft and 31.5% to airline operations.

Late-arriving aircraft 44.8% Airline operations 31.5% Air traffic & airport volume 20.4% Severe weather 3.2% Security 0.1%
  • Late-arriving aircraft 44.8%
  • Airline operations 31.5%
  • Air traffic & airport volume 20.4%
  • Severe weather 3.2%
  • Security 0.1%

Late-arriving aircraft is the knock-on category: the plane came in late, so it went out late again. It is why a 7am problem in Newark is still a problem in Denver at dinnertime, and why it is usually the biggest slice on the bar.

If you are connecting through SFO

Of 422,186 scheduled arrivals into SFO, 72.1% reached the gate less than 15 minutes behind schedule. Of the 112,695 arrivals that ran late, 53.9% were no more than 45 minutes behind — which is the difference between a tight connection and a new boarding pass.

Work out a specific layover — pick the airport and the minutes you have, and the tool reads the same arrival records back as a share.

Busiest routes out of SFO

Ranked by flights, with the share that arrived on time at the far end. Where a route carries enough flights for a page of its own the chip goes there; otherwise it goes to the destination airport.

SFO in one number

San Francisco (SFO)

Rank 14 of 363 US airports by departures. Steadiest stretch of the day: 6–8am. Hardest month: June.

July 2023–June 2026 · 417,802 departures flown

78.7% of departures left on time

Questions about SFO

What is the best time of day to fly out of San Francisco?
6–8am. Departures in that band left on time 93% of the time across 43,047 flights, July 2023 through June 2026 — the best of the ten bands in the day. The 2–4pm band was the weakest at 69.5%.
Is the early flight out of SFO really more reliable?
6–8am departures from SFO left on time 93% of the time across 43,047 flights; 6–8pm departures, 77% across 40,745. That is a gap of 16 points, and it is the whole case for the early flight.
What is the worst month to fly out of SFO?
June: 72.4% of the departures that flew left on time, with 36,293 scheduled. September was the other end of the year at 83.9%. Each figure pools three years of that calendar month.
Which airline is most on time at SFO?
United Airlines — 81.1% of its 164,239 departures from SFO left on time. Southwest Airlines sat at the other end at 62.8% over 25,086 flights. Only airlines with at least 100 departures here are ranked. Airlines that stopped filing before June 2026 are left out of the ranking — their figures cover a shorter run of months than the rest of the table.
How often are flights cancelled at SFO?
1% of scheduled departures were cancelled over July 2023 through June 2026. Cancellations are counted against everything scheduled, not against everything that flew — a rate that looks small still adds up to real people in a rebooking line.