ORD → SFO Flight Reliability

Right now

Origin · ORDNo disruption reported

Aviation weather is not currently a factor.

Updated 07:51 UTC

Chicago airport profile →

Destination · SFONo disruption reported

Aviation weather is not currently a factor.

Updated 07:56 UTC

San Francisco airport profile →

Route reliability

July 2023 – July 2026

Route Reliability Score

53/ 100Fair

Better than 20% of comparable major US routes (4,598 compared)

Calculated from 16,116 flights. How this is calculated

On-time arrivals

71.8%

11,419 of 15,914

Cancellation rate

1.14%

184 cancelled

Median arrival delay

-3 min

Average 11.5 min

Severe delays

10.4%

60+ minutes late

Delay when late

70 min

Average, when 15+ min late

Flights analyzed

16,116

3 carriers

ORD → SFO arrives on time 71.8% of the time; the return trip, SFO → ORD, arrives on time 78.7% of the time, a 7.0-point gap between the two directions of the same city pair.

ORD → SFO spends 34.2 minutes on the ground on a 1,846-mile trip: 25.6 minutes from pushback to wheels-up at ORD and 8.5 minutes from touchdown to gate at SFO.

Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026

What stands out

Reliability on this route has fallen unusually sharply over the past year, a bigger swing than 91% of 5,368 comparable routes.

67.6% on time over the most recent 12 months (2025-08 to 2026-07), against 77.0% in the 12 months before (2024-08 to 2025-07), a change of 9.4 points.

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 5,368 in the comparison.

Why ORD → SFO flights are cancelled

July 2023 – July 2026

ORD → SFO cancelled 184 of 16,116 scheduled flights — about 1 in every 88. The reason filed most often was the airline, 60.9% of the cancellations coded on this route — about 1 in every 144 scheduled flights.

Share of cancellations

Airline60.9%

Weather35.9%

Air traffic3.3%

Security0.0%

Of 184 cancelled departures carrying a reason code.

What each reason means

The airline1 in 144

Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.

112 cancellations, 60.9% of the total.

Extreme weather1 in 244

Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.

66 cancellations, 35.9% of the total.

The air traffic system1 in 2,686

Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.

6 cancellations, 3.3% of the total.

Security—

A terminal evacuation, a security breach, screening equipment failure, or screening queues over 29 minutes.

0 cancellations, 0.0% of the total.

Reason codes are the operating airline’s own filing with US DOT, not an independent finding of fault. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.

184 coded cancellations were recorded on ORD → SFO; the section appears from 50.

When it goes wrong

July 2023 – July 2026

One arrival in ten is worse than

61 min late

against a median of 3 min early

Arrived an hour or more late10.4%

Typical delay when late70 min

Cancelled1.14%

Landed somewhere else0.11%

ORD → SFO has an average that understates its risk: a typical arrival is 3 min early, but the worst tenth are 64 minutes worse than that. If the trip has something unmissable at the end of it, the median is the wrong number to plan against.

Percentiles over 16,116 operations; cancelled and diverted flights are counted separately.

Will your connection be tight enough?

Layovers at SFO after arriving from ORD.

Connection buffer and chance of missing by layover length, ORD → SFO arrivals
Connection time	Chance of missing	Reads as
30 min	45%	Likely to miss
45 min	27%	High risk
60 min	19%	High risk
90 min	10%	Some risk
120 min	6.1%	Some 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 1.14% of the time and diverts 0.11% of the time, which a late arrival never shows up in.

Chance of missing is the share of 15,914 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 61 minutes late (90th-percentile gate arrival delay), over 16,116 operations.

Any other layover length: connection checker.

Best time to fly

ORD → SFO flights departing 5–9 AM arrived on time 83.8% of the time, against 57.2% for 6–9 PM departures, a gap of 26.6 percentage points.

By day and hour

On-time arrival rate for each weekday and scheduled departure hour, in local time at the departure airport (ORD).

Hour of departure matters more than day of the week: hourly averages sit a typical 10.3 points from the route-wide rate, weekday averages 2.7 points.

On-time arrival rate for ORD to SFO by weekday and scheduled departure hour, local time. Each button reads out one slot.
Hour	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
6 AM–7 AM
7 AM–8 AM
8 AM–9 AM
9 AM–10 AM
10 AM–11 AM
11 AM–12 PM
12 PM–1 PM
1 PM–2 PM
2 PM–3 PM
3 PM–4 PM
4 PM–5 PM
5 PM–6 PM
6 PM–7 PM
7 PM–8 PM
8 PM–9 PM
9 PM–10 PM

On-time rate, % · stronger color, fewer on time

40–49
50–59
60–69
70–79
80–89
90–99

Fewer than 120 flights, not scored

Source: FlyerIntel analysis of US DOT BTS data · July 2023 – July 2026 · On time is arrival within 15 minutes of schedule. Cells round to whole percentages; the table shows one decimal.

No slot is named best or worst: too few reach 500 flights. Departures after 10 PM (82 flights) are not drawn: no slot in those hours has enough flights to score.

View as tableHide table

On-time arrival rate (%) with flights beneath, by scheduled departure hour and weekday for ORD to SFO. A dash means fewer than 120 flights, which are not scored.
Hour	Monday	Tuesday	Wednesday	Thursday	Friday	Saturday	Sunday
6 AM–7 AM	86.0% on time215 flights	92.4% on time200 flights	90.5% on time194 flights	91.9% on time210 flights	86.0% on time218 flights	90.3% on time179 flights	91.5% on time194 flights
7 AM–8 AM	86.8% on time151 flights	90.1% on time134 flights	119 flights, too few to score	85.1% on time155 flights	93.8% on time148 flights	86.3% on time142 flights	88.2% on time148 flights
8 AM–9 AM	75.8% on time237 flights	77.4% on time228 flights	76.7% on time238 flights	76.9% on time239 flights	70.6% on time242 flights	79.2% on time222 flights	74.3% on time245 flights
9 AM–10 AM	88 flights, too few to score	88 flights, too few to score	87 flights, too few to score	86 flights, too few to score	94 flights, too few to score	70 flights, too few to score	86 flights, too few to score
10 AM–11 AM	69.0% on time148 flights	75.2% on time141 flights	67.9% on time134 flights	76.6% on time146 flights	65.1% on time152 flights	72.8% on time138 flights	79.6% on time141 flights
11 AM–12 PM	61 flights, too few to score	62 flights, too few to score	59 flights, too few to score	65 flights, too few to score	54 flights, too few to score	48 flights, too few to score	67 flights, too few to score
12 PM–1 PM	71.1% on time182 flights	82.4% on time176 flights	76.3% on time174 flights	80.7% on time177 flights	73.6% on time182 flights	82.1% on time172 flights	70.9% on time182 flights
1 PM–2 PM	77 flights, too few to score	70 flights, too few to score	66 flights, too few to score	82 flights, too few to score	74 flights, too few to score	85 flights, too few to score	72 flights, too few to score
2 PM–3 PM	81.9% on time152 flights	80.0% on time145 flights	74.8% on time148 flights	80.1% on time151 flights	75.7% on time153 flights	86.3% on time133 flights	70.6% on time156 flights
3 PM–4 PM	69.6% on time149 flights	80.3% on time137 flights	72.6% on time135 flights	64.3% on time155 flights	69.3% on time154 flights	79.4% on time144 flights	70.7% on time150 flights
4 PM–5 PM	70.3% on time157 flights	80.4% on time166 flights	72.4% on time168 flights	68.0% on time151 flights	64.6% on time151 flights	74.6% on time140 flights	68.7% on time153 flights
5 PM–6 PM	111 flights, too few to score	105 flights, too few to score	104 flights, too few to score	101 flights, too few to score	103 flights, too few to score	72 flights, too few to score	88 flights, too few to score
6 PM–7 PM	58.2% on time204 flights	63.8% on time199 flights	54.3% on time198 flights	53.0% on time205 flights	56.8% on time203 flights	59.8% on time194 flights	59.7% on time217 flights
7 PM–8 PM	54.7% on time143 flights	67.4% on time131 flights	58.8% on time120 flights	56.6% on time139 flights	61.0% on time142 flights	64.4% on time147 flights	48.6% on time146 flights
8 PM–9 PM	57.5% on time162 flights	64.6% on time131 flights	55.8% on time147 flights	44.6% on time167 flights	49.1% on time173 flights	59.1% on time152 flights	55.8% on time174 flights
9 PM–10 PM	64.6% on time132 flights	93 flights, too few to score	72.4% on time130 flights	56.3% on time147 flights	66.4% on time135 flights	81 flights, too few to score	65.5% on time146 flights

By departure window

5–9 AM83.8%

9 AM–12 PM72.0%

12–3 PM76.1%

3–6 PM69.4%

6–9 PM57.2%

9 PM–5 AM67.5%

By departure hour

12 AM

3 AM

6 AM

9 AM

12 PM

3 PM

6 PM

9 PM

Why ORD → SFO runs late

July 2023 – July 2026

Late-arriving aircraft39.3%

the inbound aircraft was late, so this flight started late

The airline28.5%

crew, maintenance, boarding and fueling, all within the carrier’s control

Air traffic control27.8%

airspace and airport capacity, including weather-driven flow control

Weather4.3%

weather severe enough to stop this flight specifically

Security<0.1%

screening or terminal security incidents

Share of the delay minutes US DOT attributed to each cause for ORD → SFO. Only delays of 15 minutes or more are attributed.

Late-arriving aircraft is the largest cause on ORD → SFO, at 39.3%: flights here mostly leave late because the plane came in late, and the day shows it: 5–9 AM departures arrived on time 83.8% of the time and 6–9 PM departures 57.2%.

How this route holds up in bad weather

July 2023 – July 2026

The harder-hit end is the one the flight leaves from, where a cancellation keeps it from departing at all. Bad weather cancels 5.5 times the normal rate at ORD against 1.7 times at SFO. Cancelled in bad weather against normal hours: ORD 6.5% against 1.2%, SFO 1.5% against 0.9%. Flights that did leave ORD in bad weather arrived on time 55.7% of the time, against 77.1% in normal hours.

Bad weather and normal hours at the airports

Scheduled departures, July 2023 – July 2026

Departures from ORD and SFO in hours of bad weather and in normal hours
Departures from	ORD	SFO
Cancelled in bad weather	6.5%	1.5%
Cancelled in normal hours	1.2%	0.9%
Arrived on time, bad weather	55.7%	73.0%
Arrived on time, normal hours	77.1%	79.8%
Departures in bad weather	104,455	36,006

United Airlines (3.5% cancelled against 7.4% for the other carriers at ORD), Alaska Airlines (4.1% cancelled against 6.5% for the other carriers at ORD) and American Airlines (5.4% cancelled against 6.7% for the other carriers at ORD) cancelled fewer departures from ORD in bad weather than the other carriers there did in the same months. None of the route’s other carriers was clearly worse.

This route’s airlines in bad weather at ORD

All departures from ORD

Cancellation rates in bad weather at ORD for the airlines that fly ORD to SFO, against the other carriers at ORD in the same months
Airline	Bad-weather departures	Cancelled	Other carriers
United Airlines	31,269	3.5%below the others	7.4%
Alaska Airlines	971	4.1%below the others	6.5%
American Airlines	17,789	5.4%below the others	6.7%

These are airport figures, not route figures: every scheduled departure from ORD and SFO, to any destination, in hours the weather report called bad. The airline rows count each carrier’s departures from ORD on every route.

Weather source and limits. In full: ORD (airlines), SFO, What Weather Costs Each Airport, Who Cancels More When the Weather Turns, Airports That Change Places When Weather Turns.

Airlines on this route

Carriers with at least 200 flights, by the airline that operated each one.

Airlines on this route
Carrier	Flights	On time	Cancelled	Median delay	Severe
United Airlines	10,957	74.2%	1.01%	-4 min	9.6%
American Airlines	4,162	66.5%	1.30%	0 min	12.3%
Alaska Airlines	997	66.8%	1.91%	-1 min	11.5%

United Airlines flew 68.0% of the 16,116 flights listed.

United Airlines arrived on time 7.7 percentage points more often than American Airlines on this route.

Flights on this route

Flight numbers with at least 600 operations here and still on the schedule.

Flights on this route
Flight	Scheduled	Operations	On time
AA1253 American Airlines	3:17 PM	722	73.0%
UA1577 United Airlines	2:35 PM	694	76.4%

Weekly and seasonal patterns

By day of week

Mon70.4%

Tue76.4%

Wed71.8%

Thu70.1%

Fri68.8%

Sat75.6%

Sun69.9%

Tuesday is historically the most reliable day and Friday the least, a gap of 7.6 percentage points.

By month

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

June is historically the weakest month and September the strongest, a spread of 19.4 percentage points.

Reliability over time

July 2023 – July 2026

24

25

26

Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 67.6% against 77.0% in the 12 months before — declining by 9.4 percentage points.

Data and methodology

Calculated by FlyerIntel from 16,116 ORD → SFO 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

Analysis last recomputed September 26, 2026

ORD airport SFO airport Return direction SFO → ORD

ORD→SFO

Right now

Route reliability

What stands out

Why ORD → SFO flights are cancelled

Share of cancellations

What each reason means

When it goes wrong

Will your connection be tight enough?

Best time to fly

By day and hour

By departure window

By departure hour

Why ORD → SFO runs late

How this route holds up in bad weather

Bad weather and normal hours at the airports

This route’s airlines in bad weather at ORD

Airlines on this route

Flights on this route

Weekly and seasonal patterns

By day of week

By month

Reliability over time

Data and methodology