Passaic County, NJ Accessory Structures: ADU Rules (2026)

New Jersey is a strong home-rule state. The Municipal Land Use Law (MLUL), codified at N.J.S.A. 40:55D-1 et seq. and originally adopted as P.L. 1975 c. 291, delegates almost all residential zoning authority — including ADUs (also called accessory apartments or in-law suites) — to the governing body of each municipality. Passaic County, as a county government, does not issue residential zoning permits or set ADU standards. As of 2026, no state law forces NJ municipalities to allow ADUs by right (statewide ADU bills such as S1106 and A2792 in the 2024-2025 session remained pending), so each of Passaic County's 16 municipalities — including Paterson, Clifton, Passaic, Wayne, West Milford, Hawthorne, Little Falls, Pompton Lakes, Ringwood, Wanaque, Bloomingdale, Haledon, Prospect Park, North Haledon, Totowa, and Woodland Park — can permit, restrict, or prohibit ADUs through its own zoning ordinance under N.J.S.A. 40:55D-62. Building permits for any ADU still go through the local Construction Official under the NJ Uniform Construction Code (N.J.A.C. 5:23), not the county. Property owners must check their specific town's zoning code before designing or applying.