How many active volcanoes are there in the United States?

U.S. Geological Survey Volcano Hazards Program FAQs:

"There are about 169 volcanoes in the United States that scientists consider active. Most of these are located in Alaska, where eruptions occur virtually every year. Others are located throughout the west and in Hawaii (see our Volcano Activity Map for their locations). Kilauea volcano in Hawaii is one of the most active volcanoes on Earth. It has been erupting almost continuously since 1983."

Learn More

• U.S. Volcanoes and Current Activity Alerts (Map Tool), U.S. Geological Survey
  Interactive map showing the location and activity levels of all volcanoes in the United States and its territories

• Volcano Notification Service (Notification Service), U.S. Geological Survey
  Sign-up page for a free service offering notifications about volcanic activity at U.S. monitored volcanoes

• Smithsonian/USGS Weekly Volcanic Activity Report (Website), Smithsonian Institution
  The Smithsonian's Global Volcanism Program collaborates with the U.S. Geological Survey's Volcano Hazards Program to provide a weekly report on volcanic activity worldwide.