 Bulgaria is a unitary state . Since the 1880s , the number of territorial management units has varied from seven to 26 . Between 1987 and 1999 the administrative structure consisted of nine provinces ( oblasti , singular oblast ) . A new administrative structure was adopted in parallel with the decentralisation of the economic system . It includes 27 provinces and a metropolitan capital province ( Sofia @-@ Grad ) . All areas take their names from their respective capital cities . The provinces subdivide into 264 municipalities . 
