Mapping Affordable Housing Supported by the 421-a Tax Exemption Program
Of the residential properties in New York City that currently benefit from a 421-a tax exemption, we find that 14.8% have at least some on-site affordable units and another 4.4% supported off-site affordable housing. These properties house 50.9% of units currently in the 421-a program. Buildings receiving a 421-a exemption but not subject to an affordable housing requirement comprise 78.5% of 421a buildings but account for only 46.8% total units in the program.
From 1971 to January 2016, New York City’s 421-a tax program offered a property tax exemption for the construction of new residential buildings. Starting in the 1980s, New York City began requiring certain participating residential buildings to support the creation of affordable housing in order to benefit from the tax exemption.
While the 421-a program has been in suspension since January 16, 2016 for new developments, the program remains in effect for existing buildings throughout the city that qualified under prior iterations of the program. Some properties qualified for the tax exemption by creating affordable housing on-site while others did so by creating affordable housing off-site. Others received the tax exemption without supporting the creation of any new affordable housing. See “ENDNOTE” for details on how we classified these properties.
We also identify the properties that house the “off-site” affordable units -- properties developed in order for a fully market-rate building elsewhere in the city to receive a 421-a tax exemption. There are 37 properties, primarily located in the Bronx, that fall into this category. Of those, 22 have a 421-a exemption. The other 15 properties (including 1,728 affordable and/or market-rate units) contained off-site affordable units but do not have their own 421-a exemption. View interactive map of 421-a properties >>
CoreData.nyc is New York City’s housing and neighborhoods data hub, presented by the NYU Furman Center.
In order to estimate the affordability status of properties currently benefiting from a 421-a exemption, we use data from CoreData.nyc’s Subsidized Housing Database and consider the 421-a legislative rules (NY Real Prop Tax L § 421-A (2006) and NY Real Prop Tax L § 421-A (2014)).
We classify properties into mutually exclusive categories based on the following assumptions:
1. Supported on-site affordable units:
- The property is on a tax block adjacent to or below 110th street in Manhattan and has an exemption length of 20 or 25 years; or
- The property has an exemption length of 25 years and is not located in a part of the city formerly eligible for a 25-year exemption without the provision of affordable housing;* or
- The property received a 25-year exemption and is located in part of the city formerly eligible for a 25-year exemption without the provision of affordable housing but had to provide affordable housing because construction began after the date of a program change;* or
- The property has an additional subsidy that is tied to the provision affordable housing.
2. Supported off-site affordable units:
- The property has a 10-year exemption that began in 2013** or later and is on a tax block adjacent to or below 110th street in Manhattan; or
- The property has a 15-year exemption that began in 2013** or later and the property is inside the 2008-2016 Geographic Exclusion Area; or
- The property has a 10-year exemption and was built in the pre-2008 Geographic Exclusion Area; or
- The property is in the Greenpoint-Williamsburg GEA and contains no affordable units but is part of a larger project that includes affordable units.
3. Supported no affordable units:
- The property has an exemption of 10 or 15 years and is otherwise not determined to have supported the creation of on-site or off-site affordable units; or
- The property has an exemption of 25 years, is located in a part of the city formerly eligible for a 25-year exemption without the provision of affordable housing, began receiving the 25-year exemption in 2011 or earlier, and is otherwise not determined to have supported on-site or off-site affordable units.*
4. Construction Period:
- The property has an exemption of 3 years to cover a period of construction.
*In certain parts of the city outside of the pre-2008 Geographic Exclusion Area (GEA), some properties were able to obtain a 25-year exemption without a requirement to support the creation of affordable housing if construction began by December 27, 2007.
**The change of the GEA became effective for construction beginning July 1, 2008 or later. We assume that a property may have been grandfathered into the old program if it had a construction period of 2009 through 2011 and began receiving the 10- or 15-year exemption in 2012. Therefore, to capture properties that have supported the creation of affordable housing off-site, we look at properties with a 10-year or 15-year exemption start year of 2013 and later.