Magnitude 4.3 quake rattles San Ramon as earthquake swarm returns

At least eight quakes have rattled the East Bay city.

Feb. 2, 2026 at 9:47am by Ben Kaplan

Got story updates? Submit your updates here. ›

A magnitude 4.3 temblor hit San Ramon on Monday morning as a series of quakes shook the area. In total, eight quakes hit the region on Monday ranging from magnitude 2.5 to 4.3, with the first striking just before 6:30 a.m. This comes after the area experienced hundreds of earthquakes over magnitude 2.0 in November and December 2025, rattling city residents for weeks.

Why it matters

Earthquake swarms can be concerning for residents and disruptive to daily life, especially in a region like the Bay Area that is prone to seismic activity. Monitoring these quakes and understanding the patterns is important for public safety and preparedness.

The details

The largest quake on Monday hit just after 7 a.m. about four miles east south east of San Ramon. According to the U.S. Geological Survey, the first quake was felt by hundreds of people in the Bay Area, including those in San Francisco, Sunnyvale and Marin.

  • The first quake struck just before 6:30 a.m. on Monday, February 2, 2026.
  • The largest quake, a magnitude 4.3, hit just after 7 a.m. on Monday, February 2, 2026.
  • In 2025, the area experienced hundreds of earthquakes over magnitude 2.0 in November and December.

The players

U.S. Geological Survey

The U.S. Geological Survey is a scientific agency of the United States government that studies the landscape of the U.S., its natural resources, and the natural hazards that threaten it.

Got photos? Submit your photos here. ›

The takeaway

Earthquake swarms are a concerning phenomenon for Bay Area residents, highlighting the need for continued monitoring, preparedness, and resilience in the face of seismic activity. Understanding the patterns and impacts of these quakes is crucial for public safety.