The B class was a class of nine destroyers of the British Royal Navy, ordered as part of the 1928 Naval Estimates, launched in 1930 and that commissioned in 1931. The class was similar to the preceding A class, with minor modifications. They saw extensive service in the Second World War and five were sunk in combat; Blanche had the unfortunate distinction of being the first British destroyer lost during the war, when she was mined in the Thames Estuary some 2 months after the declaration of war.