Route profile
IAD→SFO
Flight reliability, delays and best times to fly from Washington to San Francisco, 2,419 miles.
Right now
Aviation weather is not currently a factor.
Aviation weather is not currently a factor.
Route reliability
July 2023 – July 2026
Better than 53% of comparable major US routes (4,598 compared)
Calculated from 8,482 flights. How this is calculated
IAD → SFO arrives on time 78.5% of the time; the return trip, SFO → IAD, arrives on time 81.9% of the time, a 3.4-point gap between the two directions of the same city pair.
IAD → SFO spends 29.7 minutes on the ground on a 2,419-mile trip: 21.2 minutes from pushback to wheels-up at IAD and 8.4 minutes from touchdown to gate at SFO.
Source: US DOT Bureau of Transportation Statistics · Data covering July 2023 – July 2026
What sets this route apart
Where IAD to SFO differs most from similar routes by hour, weekday, month and airline, July 2023 – July 2026.
IAD to SFO struggles most at 5 PM: 54.7% of its flights scheduled then arrive on time, 17.9 points behind the 72.6% on routes of similar length at the same hour. Against all other routes the gap is 15.1 points.
IAD to SFO is at its best against routes of similar length for flights scheduled at 4 PM: 83.8% arrive on time, 9 points ahead of the 74.8% those routes manage at that hour. Against all other routes the gap is 13.1 points.
In February, IAD to SFO runs 5.4 points below routes of similar length, 75.2% on time to 80.6%. Against all other routes the gap is 6.3 points.
March is kinder to IAD to SFO than to routes of similar length: 84.1% on time against 79.1%, 5 points better. Against all other routes the gap is 6.2 points.
Alaska Airlines’ flights on IAD to SFO arrive on time 71.9% of the time, 4.2 points below the 76.1% it manages on its routes of similar length. Against all other routes the gap is 6.1 points.
IAD to SFO against comparable routes
July 2023 – July 2026| Measure | This route | Compared with | Them | Gap | Flights behind it |
|---|---|---|---|---|---|
| Hour: 5 PM departures | 54.7% | routes of similar length | 72.6% | −17.9 pts | 576 here, 57,586 there |
| Hour: 4 PM departures | 83.8% | routes of similar length | 74.8% | +9.0 pts | 458 here, 53,277 there |
| Month: February | 75.2% | routes of similar length | 80.6% | −5.4 pts | 513 here, 71,785 there |
| Month: March | 84.1% | routes of similar length | 79.1% | +5.0 pts | 641 here, 86,201 there |
| Airline: Alaska Airlines | 71.9% | routes of similar length | 76.1% | −4.2 pts | 959 here, 170,422 there |
Each comparison pools the flights of other routes, with this route’s own left out. Similar length means within 15% of this route’s 2,419 miles, with at least 5 such routes. A bucket is set against the most comparable group that has enough flights: similar length, then the same origin (at least 3 routes), then all other routes. Hours, weekdays and months appear only where both sides have 120 completed flights, and airlines where both have 600. The gap must be at least 2 points and 2 standard errors, and only the largest gap each way is kept per measure. These are differences in the flights counted, not causes.
Why IAD → SFO flights are cancelled
July 2023 – July 2026
IAD → SFO cancelled 83 of 8,482 scheduled flights — about 1 in every 102. The reason filed most often was the airline, 75.9% of the cancellations coded on this route — about 1 in every 135 scheduled flights.
Share of cancellations
Of 83 cancelled departures carrying a reason code.
What each reason means
Crew, maintenance, aircraft cleaning, baggage or fueling: what BTS counts as within the carrier’s own control.
63 cancellations, 75.9% of the total.
Conditions the carrier judged severe enough to stop the flight: a blizzard, a hurricane, a line of thunderstorms.
19 cancellations, 22.9% of the total.
Airport capacity, air traffic control flow programs, heavy traffic and ordinary bad weather. A system decision, not the airline’s.
1 cancellation, 1.2% of the total.
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. With only one or two carriers on the route, the split mostly reflects how they file. Ordinary bad weather is filed under air traffic, so weather’s full share is larger than its bar.
83 coded cancellations were recorded on IAD → SFO; the section appears from 50.
When it goes wrong
July 2023 – July 2026
43 min late
against a median of 7 min early
Percentiles over 8,482 operations; cancelled and diverted flights are counted separately.
Will your connection be tight enough?
Layovers at SFO after arriving from IAD.
| Connection time | Chance of missing | Reads as |
|---|---|---|
| 30 min | 37% | Likely to miss |
| 45 min | 21% | High risk |
| 60 min | 13% | Some risk |
| 90 min | 7.4% | Some risk |
| 120 min | 4.6% | Low 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 0.98% of the time and diverts 0.18% of the time, which a late arrival never shows up in.
Chance of missing is the share of 8,384 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 43 minutes late (90th-percentile gate arrival delay), over 8,482 operations.
Any other layover length: connection checker.
Best time to fly
IAD → SFO flights departing 9 AM–12 PM arrived on time 86.0% of the time, against 67.1% for 6–9 PM departures, a gap of 18.9 percentage points.
By departure window
By departure hour
- 12 AM to 5 AM: too few flights to score
- 6 AM: 87.3% on time from 903 flights
- 7 AM: 86.4% on time from 492 flights
- 8 AM: 82.1% on time from 1,240 flights
- 9 AM: 85.8% on time from 170 flights
- 10 AM to 11 AM: too few flights to score
- 12 PM: 83.1% on time from 1,127 flights
- 1 PM: too few flights to score
- 2 PM: 81.3% on time from 725 flights
- 3 PM: 76.1% on time from 209 flights
- 4 PM: 83.8% on time from 463 flights
- 5 PM: 54.7% on time from 586 flights
- 6 PM: 67.0% on time from 901 flights
- 7 PM: 69.7% on time from 486 flights
- 8 PM: 60.2% on time from 178 flights
- 9 PM: too few flights to score
- 10 PM: 83.5% on time from 993 flights
- 11 PM: too few flights to score
Why IAD → SFO runs late
July 2023 – July 2026
the inbound aircraft was late, so this flight started late
crew, maintenance, boarding and fueling, all within the carrier’s control
airspace and airport capacity, including weather-driven flow control
weather severe enough to stop this flight specifically
screening or terminal security incidents
Share of the delay minutes US DOT attributed to each cause for IAD → SFO. Only delays of 15 minutes or more are attributed.
Late-arriving aircraft is the largest cause on IAD → SFO, at 33.3%: flights here mostly leave late because the plane came in late, and the day shows it: 9 AM–12 PM departures arrived on time 86.0% of the time and 6–9 PM departures 67.1%.
Airlines on this route
Carriers with at least 200 flights, by the airline that operated each one.
| Carrier | Flights | On time | Cancelled | Median delay | Severe |
|---|---|---|---|---|---|
| United Airlines | 7,512 | 79.3% | 0.97% | -7 min | 7.2% |
| Alaska Airlines | 970 | 71.9% | 1.03% | -3 min | 9.7% |
United Airlines flew 88.6% of the 8,482 flights listed.
United Airlines arrived on time 7.4 percentage points more often than Alaska Airlines on this route.
Flights on this route
Flight numbers with at least 600 operations here and still on the schedule.
| Flight | Scheduled | Operations | On time |
|---|---|---|---|
| UA1757 United Airlines | 5:55 PM | 616 | 56.1% |
Weekly and seasonal patterns
By day of week
Tuesday is historically the most reliable day and Friday the least, a gap of 7.4 percentage points.
By month
- Jan: 80.7%
- Feb: 75.2%
- Mar: 84.1%
- Apr: 80.8%
- May: 75.5%
- Jun: 70.5%
- Jul: 70.1%
- Aug: 77.3%
- Sep: 84.8%
- Oct: 88.1%
- Nov: 81.3%
- Dec: 77.6%
July is historically the weakest month and October the strongest, a spread of 18.0 percentage points.
Reliability over time
July 2023 – July 2026
- July 2023: 62.7% from 248 flights
- August 2023: 73.0% from 250 flights
- September 2023: 78.9% from 230 flights
- October 2023: 86.4% from 215 flights
- November 2023: 83.6% from 179 flights
- December 2023: 87.4% from 184 flights
- January 2024: 77.5% from 153 flights
- February 2024: 80.8% from 153 flights
- March 2024: 80.1% from 213 flights
- April 2024: 72.2% from 227 flights
- May 2024: 68.2% from 242 flights
- June 2024: 76.7% from 240 flights
- July 2024: 76.8% from 248 flights
- August 2024: 75.3% from 249 flights
- September 2024: 88.2% from 245 flights
- October 2024: 94.4% from 267 flights
- November 2024: 78.7% from 257 flights
- December 2024: 78.8% from 260 flights
- January 2025: 85.3% from 192 flights
- February 2025: 67.1% from 174 flights
- March 2025: 84.4% from 226 flights
- April 2025: 87.6% from 286 flights
- May 2025: 77.9% from 273 flights
- June 2025: 70.9% from 275 flights
- July 2025: 68.8% from 267 flights
- August 2025: 83.3% from 255 flights
- September 2025: 87.4% from 206 flights
- October 2025: 82.8% from 246 flights
- November 2025: 82.5% from 230 flights
- December 2025: 68.9% from 245 flights
- January 2026: 78.3% from 209 flights
- February 2026: 78.3% from 189 flights
- March 2026: 87.8% from 209 flights
- April 2026: 80.8% from 229 flights
- May 2026: 79.8% from 268 flights
- June 2026: 63.5% from 234 flights
- July 2026: 72.6% from 209 flights
Over the most recent 12 months (2025-08 to 2026-07), on-time arrivals averaged 78.7% against 80.0% in the 12 months before — broadly unchanged.
Data and methodology
Calculated by FlyerIntel from 8,482 IAD → 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
Related research: How Long a Layover Needs to Be · Two Airlines on One Route · Best Time of Day to Fly From Major US Airports
Analysis last recomputed