Traffic Predict
Is Bay Area Traffic Getting Worse?
In 2026, weekday freeway congestion in the San Francisco Bay Area was 4% better than in 2025 and 46% better than in 2016, measured as hours lost in stop-and-go traffic per 1,000 miles driven. Traffic volume per sensor was about the same as in 2025.
Year by year (weekdays)
| Year | Delay per 1,000 vehicle-miles | Change | Vehicles per sensor per day | Average speed | 5 pm speed | Sensors |
|---|---|---|---|---|---|---|
| 2016 (partial) | 0.97 h | – | 71,404 | 60 mph | 53 mph | 2,156 |
| 2017 | 0.90 h | -7% | 72,678 | 60 mph | 53 mph | 2,198 |
| 2018 | 0.85 h | -5% | 71,937 | 60 mph | 54 mph | 2,224 |
| 2019 | 0.86 h | +1% | 72,246 | 60 mph | 53 mph | 2,256 |
| 2020 | 0.31 h | -65% | 61,563 | 62 mph | 59 mph | 2,269 |
| 2021 | 0.35 h | +16% | 67,450 | 61 mph | 57 mph | 2,314 |
| 2022 | 0.38 h | +7% | 68,921 | 61 mph | 56 mph | 2,335 |
| 2023 | 0.57 h | +50% | 70,042 | 60 mph | 55 mph | 2,337 |
| 2024 | 0.58 h | +2% | 69,986 | 60 mph | 55 mph | 2,351 |
| 2025 | 0.55 h | -5% | 70,949 | 60 mph | 55 mph | 2,440 |
| 2026 | 0.53 h | -4% | 70,673 | 60 mph | 54 mph | 2,246 |
Month by month
Freeway by freeway, 2016 vs 2026
| Freeway | 2016 | 2026 | Change |
|---|---|---|---|
| I-80 East | 1.08 h | 0.70 h | -35% |
| I-80 West | 1.15 h | 0.57 h | -50% |
| I-238 South | 0.81 h | 0.36 h | -56% |
| I-280 North | 1.08 h | 0.24 h | -78% |
| I-280 South | 1.18 h | 0.46 h | -61% |
| I-580 East | 0.78 h | 0.56 h | -28% |
| I-580 West | 0.37 h | 0.49 h | +33% |
| I-680 North | 0.83 h | 0.55 h | -33% |
| I-680 South | 0.65 h | 0.24 h | -63% |
| I-780 East | 0.00 h | 0.00 h | – |
| I-780 West | 0.00 h | 0.02 h | – |
| I-880 North | 1.46 h | 0.75 h | -49% |
| I-880 South | 1.04 h | 0.59 h | -43% |
| I-980 East | 0.05 h | 0.01 h | -81% |
| I-980 West | 0.05 h | 0.02 h | -63% |
| SR-4 East | 0.61 h | 0.27 h | -55% |
| SR-4 West | 1.11 h | 0.69 h | -37% |
| SR-17 North | 0.26 h | 0.13 h | -49% |
| SR-17 South | 0.32 h | 0.04 h | -87% |
| SR-24 East | 1.88 h | 1.49 h | -21% |
| SR-24 West | 0.48 h | 0.21 h | -56% |
| SR-25 North | 0.04 h | 0.15 h | +253% |
| SR-25 South | 1.56 h | 1.42 h | -9% |
| SR-29 North | 0.00 h | 0.00 h | – |
| SR-37 East | 3.35 h | 0.09 h | -97% |
| SR-37 West | 1.89 h | 0.00 h | -100% |
| SR-85 North | 1.54 h | 0.75 h | -51% |
| SR-85 South | 1.86 h | 1.42 h | -24% |
| SR-87 North | 0.98 h | 0.79 h | -20% |
| SR-87 South | 0.42 h | 0.26 h | -39% |
| SR-92 East | 2.05 h | 1.34 h | -35% |
| SR-92 West | 0.90 h | 0.34 h | -62% |
| SR-152 East | 0.36 h | 0.47 h | +31% |
| SR-152 West | 0.29 h | 0.05 h | -82% |
| SR-156 East | 0.00 h | 0.08 h | – |
| SR-156 West | 0.12 h | 0.12 h | -4% |
| SR-160 North | 0.08 h | 0.00 h | -100% |
| SR-237 East | 2.89 h | 3.37 h | +17% |
| SR-237 West | 0.65 h | 0.14 h | -79% |
| SR-242 North | 1.63 h | 1.34 h | -18% |
| SR-242 South | 1.67 h | 0.97 h | -42% |
| SR-948 South | 1.15 h | 0.00 h | -100% |
| US-101 North | 0.71 h | 0.38 h | -46% |
| US-101 South | 1.01 h | 0.75 h | -26% |
Weekday delay per 1,000 vehicle-miles on each freeway direction within the San Francisco Bay Area. 14 freeway directions are left out because the sensors reporting changed too much between the two years to compare fairly.
How this is measured
Every hour, road sensors report how many vehicles passed and how fast they went. For each sensor we multiply the vehicles by the length of freeway it covers to get vehicle-miles, and count the extra time spent below 35 mph as delay. Dividing delay by miles driven gives a congestion measure that doesn't change just because sensors are added or retired. Only weekdays with at least 20 hours of data are used. Data: Caltrans PeMS.
See also: how rain slows Bay Area traffic, by time of day and how hard it rains.