In late March and early April 2017 Public Health Seattle King County (PHSKC) and the Washington Department of Health investigated an outbreak of norovirus among customers who consumed raw oysters at different Seattle restaurants. Cases were part of three different dining parties. Meal dates ranged from March 26 to April 1. Case patients included visitors from California and Wisconsin. One person was laboratory confirmed with norovirus. No one was hospitalized and no one died. The outbreak was traced to raw oysters from the same oyster harvesting area, Bay Center.