Parking Minimums Are the Hidden Tax: The Zoning Reform Spreading City to City

Parking is the quietest line item that can kill a housing deal. Minimum parking requirements don’t just mandate asphalt—they mandate cost, delay, and building form. They change what can fit on a lot, what a lender will finance, and what a builder can deliver at a price the market can absorb.

That’s why parking reform has become one of the fastest-moving zoning changes in the U.S.

A useful benchmark: researchers tracking zoning codes nationally have found that roughly 20% of examined codes have abolished or reduced parking mandates citywide, while many others have done partial reforms limited to small areas like downtowns. This is the difference between symbolic reform and structural change. If you only waive parking on two blocks, you haven’t changed the housing system—you’ve created an exception zone.

Why does removing parking minimums matter so much? Because parking is expensive (especially structured parking), and those costs flow straight into rent, sales price, or subsidy requirements. Regional planning research has documented that waiving parking requirements can yield more affordable homes on smaller parcels—precisely the kind of “missing middle” sites that cities say they want to activate. In other words: if your zoning forces parking, you’re forcing a building typology—and often forcing it to be larger, pricier, and less flexible.

In 2025, the political story has also shifted. Parking reform used to be a planning-school favorite and a neighborhood fear.

Now it’s increasingly framed as an affordability tool, a transit tool, and a permitting tool. A good example: Denver debated eliminating minimum parking mandates as part of a broader push to reduce cost and bureaucracy, with supporters arguing it improves affordability and speeds approvals. Even when proposals face opposition over curb crowding, the center of gravity has moved: the burden is increasingly on defenders of minimums to explain why “required parking” is worth the housing tradeoff.

So what replaces parking minimums? The best reforms don’t pretend cars vanish. They shift from mandates to performance and management:

• Contextual design (right-sizing parking based on neighborhood demand, not one-size rules)

• Shared parking agreements and district garages

• Curb management (pricing, permits, loading zones)

• Transit-oriented standards (less parking near high-frequency transit)

• Bike and micromobility storage that actually reduces car dependence

Zoning is now catching up to what markets already do: many urban projects build less parking than old codes required, especially near transit. Minimums simply force developers to buy and pour a product people may not want at that scale—and to charge them for it anyway.

For OUM’s zoning lens, the point is bigger than parking. Parking reform is the gateway push towards modern zoning. It forces cities to admit a hard truth: rules written for a 1970s driving paradigm can’t produce 2026 affordability outcomes. It also shows how “small” code changes can unlock real unit count—not by changing height, but by changing the physics of feasibility on constrained lots.

Zoning for Opportunity