B&Bs belong to the 43rd category, specifically as follows:

431 provides catering, accommodation services

Accommodation agents (hotels, boarding houses for meals) 434, caterers 431, cafes 4324, cafeterias 4325, restaurants 4327, and temporary accommodations for rent 434. Boarding room reservation 4314, hotel reservation 4315, cafeteria 4317, fast food restaurant 4318, bar service 43138, holiday camping accommodation service 43145, temporary accommodation reservation 43162, motel 43183, food carving 43193, mobile food supply.