Nonconforming Use Law and Legal Definition

Nonconforming use is a term used in zoning laws to refer to the existing use (residential, commercial, agricultural, light industrial, etc.) of a parcel of real property which is zoned for a more limited or other use in the city or county's general plan. Usually such use is permitted only if the use existed on the property before the adoption of the zoning ordinance which it violates.

A nonconforming use is an existing structure or use of a property which is not permitted under the current zone designation. Generally speaking, a use might become nonconforming through the adoption of changes to a zone to reflect new laws, or as the result of court case decisions. For example, an existing food store that was established 20 years ago on a parcel currently zoned Rural Residential would be considered a nonconforming use. Lawfully established nonconforming uses are allowed to continue, but are subject to limitations. They may be “frozen” at the level of operation that existed at the time of implementation of a zone designation which made the use nonconforming.