Bay State

Bay State may refer to:


 * Massachusetts, nickname "Bay State," a U.S. state with shores on Massachusetts Bay, Cape Cod Bay, Buzzards Bay and Narragansett Bay
 * Bay State College, a private university in Boston, Massachusetts
 * Bay State Conference, a high school athletic conference in Massachusetts
 * Bay State (TV series), the Boston University-produced soap opera
 * Bay State Road, a street on the Boston University campus
 * Bay State (musical instrument brand), a brand of musical instrument made in the 19th century by John C. Haynes & Co.
 * Baystate, a Japanese jazz record label