Belknap County is a county in the U.S. state of New Hampshire. As of the 2020 census, the population was 63,705. The county seat is Laconia. It is located in New Hampshire's Lakes Region, slightly southeast of the state's geographic center. Belknap County comprises the Laconia, NH Micropolitan Statistical Area, which in turn constitutes a portion of the Boston-Worcester-Providence, MA-RI-NH-CT Combined Statistical Area.