Build Philly Now · August 2026
The Mixed-Income Neighborhoods Overlay
MIN was meant to produce affordable housing through private development. In four years it has produced 19 affordable units. Over the same period, against a market-matched control, an estimated 1,000–1,400 fewer homes were built inside the overlay. The record, in five questions.
1. Is MIN producing affordable housing?
Since taking effect in July 2022, MIN has produced 19 affordable units across 4 completed developments, per the City’s 2025 Mixed Income Housing Program Report. Of the 213 affordable units the whole mixed-income program (voluntary bonus included) has created citywide since 2017, MIN accounts for 19. Its last completion was September 2025, a year ago; none has finished since.
The pipeline is not yet housing
The City’s 2025 report lists 5 more MIN developments in the pipeline, holding 21 affordable units. None is built. Approved units are not occupied units.
The larger question is how much housing it prevented.
2. Is it costing us housing overall?
Against a market-matched control, development inside the overlay fell by more than citywide conditions explain. Housing production from large projects dropped 56.6%, from about 2,133 units a year to 926. New construction of 10+ unit buildings fell from 27.7 permits a year to 8.7. The estimated housing deterred is 1,000–1,400 units.
Each bar is annual production after MIN as a share of that area’s own pre-MIN rate. Inside the overlay it fell to 43% (2,133 → 926 units/yr); in the matched comparison area only to 68% (289 → 198). The gap between the two is the decline attributable to MIN.
Roughly as much deterred as built
Inside the overlay since July 2022, large projects account for 2,833 units permitted and 996 completed. The estimated 1,000–1,400 deterred is of the same order as what was actually built.
This might be acceptable if a mandate were the only way to obtain affordability from private development. It is not.
3. Is the mandate necessary, and can it work on its own?
Most affordable units built inside the overlay come from subsidy, not the mandate. Since July 2022, large projects inside MIN account for 466 affordable units from subsidized developments (LIHTC or public housing) and 89 from MIN’s requirement. Affordable housing in Philadelphia comes mainly through LIHTC, vouchers, and the voluntary bonus.
The MIN units that do get built typically rely on a housing voucher. HUD’s voucher payment standard exceeds MIN’s 40%-AMI rent cap in every ZIP the overlay covers.
The green dot sits above the red cap in every ZIP — a voucher pays more than MIN’s rent limit everywhere the overlay reaches, which is why the MIN units that get built lean on one. The blue-to-red distance is the full gap an unfunded mandate leaves for the market-rate units to carry.
Without a voucher, an unfunded mandate can pay for the affordable units only out of the market-rate units in the same building. That cross-subsidy works only where rents clear a break-even set by development cost. The dial below shows where each MIN neighborhood lands, for any mandate you set.
How high would rents have to go for the mandate to work?
With no public subsidy, an IZ mandate only pencils once market rents reach the self-finance zone, where the market-rate units can carry the affordable ones. The dials set the mandate — how deep, how many. The bars are each neighborhood’s real market rent, and they don’t move.
Rough band. The self-finance zone is the 2BR market rent at which the market-rate units’ margin covers the affordable discount, at roughly a 6% yield on cost across a range of all-in development cost. Hard construction cost is about the same citywide; land is the part that varies by neighborhood, and it rises with rents, so a single cost band runs generous to the mandate in the priciest areas. Rents from Zillow (Jun 2026), AMI rents from the 2025 MIR. This is cost break-even, not a bankable return: a separate 150-unit pro forma finds a financeable deal needs 2BR rents above the band, so even “breaks even” neighborhoods may not attract financing. The rigorous version is a full per-project pro forma.
If the goal is affordable units from private development, the City already runs a program that does more.
4. How does it compare with the voluntary bonus?
Philadelphia runs two programs for this: the voluntary Mixed Income Housing Bonus and the mandatory MIN overlay. The voluntary one has produced more.
| MIHB — voluntary bonus | MIN — mandate | |
|---|---|---|
| Affordable units built, since 2017 | 194 | 19 |
| Contributed to the Housing Trust Fund | $36.9M | $0 |
| Mechanism | Incentivizes added density | 20% at 40% AMI required, no subsidy |
| Fee-in-lieu option | Available | Prohibited |
The incentive has produced roughly ten times the affordable units of the mandate, and funds the trust fund the mandate does not.
The comparison matters now, because MIN’s record bears on the City’s largest housing commitment.
5. What is it doing to the H.O.M.E. Initiative?
The Parker administration’s $2 billion H.O.M.E. Initiative aims to create and preserve 30,000 homes, 13,500 of them new construction, financed partly by an $800 million bond. MIN works against it three ways.
Supply
The 1,000–1,400 units deterred equal about 9% of the 13,500-unit new-construction target, from two council districts.
Money
The plan borrows an $800 million bond to fund affordable housing. MIN’s fee-in-lieu ban forgoes trust-fund revenue that costs nothing to raise.
Transit
MIN removes the Transit-Oriented Communities bill’s density bonus by statute, about 1,364 fewer units near transit.
The record points to one conclusion.
Fund it, or repeal it.
An unfunded mandate has no budget. It hands the cost of the affordable units to the developer and hopes the market absorbs it; where it doesn’t, the units go unbuilt. Two responses fit the evidence, and this analysis favors neither: fund the affordability, or drop the requirement. The one the evidence rejects is treating the mandate as free.
That cost is estimable. Renting a 2-bedroom at each affordability level instead of at market takes roughly this monthly subsidy in the average MIN neighborhood.
| Affordability level | Allowed rent | Subsidy per unit / mo | Per unit / yr |
|---|---|---|---|
| 40% AMI (MIN's requirement) | $1,075 | $917 | $11,004 |
| 50% AMI | $1,344 | $648 | $7,776 |
| 60% AMI | $1,613 | $379 | $4,548 |
| 80% AMI | $2,150 | about $0 | about $0 |
MIN sets its requirement at the deepest level, 40% of AMI, unfunded. Shallower requirements cost far less; by 60% of AMI, much of the overlay’s market rents already meet the cap.
Other jurisdictions have addressed this
Oregon has made unfunded inclusionary zoning unlawful; Florida requires localities to offset its full cost. The shared principle: affordable units are a public good, and should be paid for publicly rather than mandated for free.