Kyustendil Province is a province in southwestern Bulgaria, extending over an area of 3,084.3 km2 (1,190.9 sq mi), and with a population of 163,889. It borders the provinces of Sofia, Pernik, and Blagoevgrad; to the west, its limits coincide with the state borders between Bulgaria and North Macedonia, and between Bulgaria and the Republic of Serbia. The administrative center of the Province is Kyustendil.

Sofia Province is a province (oblast) of Bulgaria. The province does not include Sofia in its territories, but Sofia remains its administrative center. The province borders on the provinces of Pernik, Kyustendil, Blagoevgrad, Pazardzhik, Plovdiv, Lovech, Vratsa, Montana and "Sofia City Province", and borders with Serbia to the northwest.