New York’s 485x Program Spurs Larger Units and Higher Rents

Supply and Demand Lessons From Sun Belt Cities

South Florida and Austin have recently demonstrated the impact of ample multifamily development on rental pricing, according to The Real Deal. In both markets, a surge in apartment construction pushed vacancy rates higher and sent median rents down—South Florida saw a 20% decline to $2,277 after new units outpaced leases, while Austin’s rents dropped 16% to $1,296 as the city added 18,000 residents across two years. Both cities operate without the level of rent regulation seen in New York, allowing supply growth to directly influence pricing, making for a pointed contrast with New York’s policy-driven approach to affordability.

The Details

According to analysis underway by Chris Goldammer of CityTracker.ai, New York’s 485x program is incentivizing developers to stop at 99 units per project. Rather than maximize the number of units allowed by zoning, developers are building much larger apartments to fill the allocated square footage, presumably to maintain profitability within the 99-unit threshold. Goldammer’s findings show that apartments in these 99-unit 485x projects average 200 SF larger than comparable units in projects not using the incentive. For example, units that might otherwise be 750 SF are now closer to 1,100 SF, raising the rent per unit significantly. With rents averaging $85 PSF annually, that extra space translates to higher monthly costs. A 1,000 SF unit in Brooklyn’s Intrata Park Slope currently lists at $7,400 a month ($88 PSF); an additional 200 SF would push monthly rent up to $8,880 if pricing remains linear.

Development Incentives Fuel Market Distortion

The unintended consequence of the 485x cap is reshaping market incentives. Rather than producing large numbers of smaller, more affordable apartments, developers are feeding demand at the high end with units that price out many renters. Several mixed-income developments have already stalled as developers reassess project economics under the incentive’s current structure. This trend is likely to intensify competition for older, smaller units in 421a buildings, as renters unable to afford the larger, pricier 485x units look elsewhere. Meanwhile, the underlying aim of the tax incentive—to ease affordability pressure—has arguably backfired, as the policy’s structure encourages less density and higher average rents.

Why It Matters

For New York CRE players, the design of 485x is a cautionary tale in policy-driven market distortion. According to data from CityTracker.ai and The Real Deal, the program’s 99-unit incentive structure is not just capping supply but actively encouraging larger, less attainable homes. With apartments in 485x buildings averaging 200 SF more than their peers, the city’s push for affordability is instead inflating rent rolls. As construction rises under the program, fewer small units hit the market; the remaining affordable stock turns over with even more competition.

This is occurring at a time when New York’s 2023 vacancy rate hit 1.4%—a level that would trigger ‘housing emergency’ protections by law, but is rare outside highly regulated coastal cities. For context, economists generally view a 7% vacancy rate as healthy; South Florida, which reached that mark through robust construction, saw rents drop by double digits as a result. New York’s experience demonstrates how legislating supply can unintentionally limit affordability rather than enhance it. With no shortage of demand and ample job creation, housing policy design will shape both developer strategy and rental market outcomes going forward.

What’s Next

With debate around 485x likely to intensify, expect calls for reform to the program’s structure, especially regarding the hard-stop at 99 units. Stakeholders are watching as more analysis from CityTracker.ai and other researchers clarifies the program’s real-world effects on rental supply and affordability. Meanwhile, renters priced out of newer stock may shift demand to older 421a buildings or look outside city limits, further complicating New York’s ongoing housing crunch. How policymakers and developers respond could reshape the next wave of multifamily construction in the city.