Voluntary and Mandatory Inclusionary Housing differ in that Mandatory Inclusionary Housing (MIH) makes developers build affordable housing when developing in certain rezoned areas, while voluntary inclusionary housing allows developers to choose whether to provide affordable housing in exchange for zoning benefits to density and build height. Historically, Voluntary Inclusionary Housing (VIH) was New York City's primary voluntary density bonus program, however, the Universal Affordability Preference (UAP), adopted through the City of Yes for Housing Opportunity in 2024, has become the more prominent voluntary affordability incentive. Under UAP, developers must reserve at least 20% of residential floor area for households earning up to 60% of Area Median Income (AMI) in exchange for additional buildable floor area. Usually under MIH, developers provide either 25% of residential floor area at an average of 60% AMI or 20% of residential floor area at an average of 40% AMI. UAP increases buildable square footage through a density bonus, allowing developers to construct larger buildings and potentially improve project profitability, while MIH does not provide an optional density bonus and instead requires affordable housing as a condition of development. Both programs tie affordability requirements to AMI, but UAP is an incentive-based program whereas MIH functions as a regulatory requirement. (NYC Department of City Planning, Verified June 2026)