Philadelphia's residential construction abatement exempts real estate taxes on property improvements for a fixed term. Mayor Parker's proposed 20-year office-to-residential conversion abatement would apply that same mechanism to Center City's vacant office stock. This page makes the fiscal case for it.
Pennsylvania already authorized this 20-year abatement — it passed as part of the state budget in November 2025. What's still missing is Philadelphia's own ordinance putting it into effect, which Council hasn't introduced yet. Once it does, the exemption would apply to any portion of an office building, vacant school, factory, or former government building that converts to residential use — and, for buildings too deteriorated to convert directly, state law also allows for demolition and new residential construction in their place. (The city's own chief deputy solicitor has pointed to the shuttered police headquarters, the Roundhouse, as exactly this kind of case.) No geographic restriction. Some on Council have pushed for an affordable-housing set-aside; the administration says state law doesn't allow one.
vs. 2019 baseline, documented in OPA assessment data across 46 matched CCD office parcels.
Peak (2020) to 2025 — an $870M decline driven by successful Board of Revision of Taxes appeals.
Councilmember Young's district holds the decisive vote on the 42 strong and possible candidates.
Center City's office tax base peaked at $5.66B in 2020. By 2025 it had fallen to $4.79B — an $870M decline driven by a cascade of successful Board of Revision of Taxes appeals. Against the 2019 pre-pandemic baseline, matched CCD office buildings now generate $9.6M less in annual property tax revenue. That number grows each year as more appeals work through the pipeline.
Source: Philadelphia OPA via OpenDataPhilly · 46 matched CCD commercial parcels
vs. 2019
declining in 2025
since peak (2020)
Local CRE analysts argue the market hit a cyclical bottom in 2024–25. They may be right — for Class A trophies, which are stabilizing as tenants consolidate into premium space. Class B/C offices with large floor plates and 30%+ vacancy are structurally impaired regardless of cycle, and the conversion candidates are in that second category. Even under an optimistic recovery assumption, the stability case holds.
Change the assumption to see how the office/residential divergence holds up under different futures.
How to read it: every line starts at 100 in 2019. A line at 93 means that group's assessed value is 7% below where it started; 111 means 11% above.
Source: Philadelphia OPA · Residential: 200-parcel CCD sample (category_code=1) · Office: 46 matched commercial parcels · Projections illustrative
Don't compare the abatement cost to the full building value — that tax revenue is already disappearing as buildings lose tenants. And the common assumption — that an abated building pays close to nothing for a decade — doesn't hold up against actual OPA records. Land reassessment and non-exempt improvement value mean converted buildings often pay more during the abatement than they did as offices before conversion.
| Building | Pre-conv. avg/yr | During abatement avg/yr | Change |
|---|---|---|---|
| 200 N 16th St — office tower, Center City | $593,343 | $724,419 | +22.1% |
| 258–62 S Broad — POST Apartments | $496,729 | $600,477 | +20.9% |
| 3600–30 Lancaster — Lancaster Ave corridor | $62,482 | $81,959 | +31.2% |
| 2201 Bryn Mawr Ave | $144,886 | $156,124 | +7.8% |
| 323–27 N 13th St — smaller building | $41,396 | $49,486 | +19.5% |
Independently re-derived from Philadelphia's public parcel-assessment history (OPA/Carto assessments table) — land + non-exempt improvement value × that year's actual combined tax rate. Five buildings is a check on the mechanism, not a forecast, and OPA assesses new buildings two to three years late, so some "during abatement" figures reflect assessment lag. A 6th candidate (4701–29 Pine St, "Garden Court Plaza") was dropped after verification showed it's a 1926 apartment building renovated by Post Brothers, not an office conversion. Two others (1530–34 Locust St, 2201 Park Towne Pl) excluded — too few pre-conversion years for a reliable baseline. Both also showed increases on conversion.
In all 5 of these buildings, tax payments were higher during the abatement period than before conversion — average +20.3%, ranging from +7.8% to +31.2%. The abatement does not, as a rule, suppress tax revenue below pre-conversion levels: land reassessment and non-exempt improvement value lift the city's collections during the abated years even while the new or renovated improvements are partially shielded from the rolls. One caveat: 2201 Bryn Mawr Ave's +7.8% only holds through 2024 — it sold that December, and 2025–26 show the whole parcel exempt, which would flip it to −16% if those years are counted. This is a sample of 5 buildings, not a guaranteed outcome for every conversion.
The Parker administration's draft is a full 20-year exemption on improvements — 100% off for the whole term, no phase-in — and it applies only to the part of a building that converts. The calculator below measures what the city collects on a converted building against what it would have collected otherwise. How much the city comes out ahead or behind depends on how the exemption is written, so the calculator shows two designs: only the increase over the pre-conversion assessment is exempt (as in Philadelphia's current abatements, so the old base keeps paying), or all improvements are exempt and only land is taxed. Use the toggle under the controls to switch; the five conversions above show the first design in practice. A phased structure — taxes stepping in gradually over the 20 years, the way today's reformed 10-year residential abatement phases in over its own term — isn't what's drafted, but it's a real alternative Council could push for instead. Use the presets and controls below to compare both.
This calculator models direct property tax only. Wage and business tax revenue from new residents adds an estimated $800–$1,200/unit/yr. Retail and services activated by residential density add more. The full fiscal case is stronger than the property tax math alone.
The calculator above defaults to 10 buildings — a plausible early wave. But how large is the full pool of eligible buildings? We checked Philadelphia's own property records for every parcel coded as a genuine office building (not a corner store with a bank branch upstairs), at three size cutoffs.
| Pool | 20-yr cost | Avg./yr |
|---|---|---|
| Narrow 42 buildings — the strong and possible candidates, summed from each building's OPA taxable value | $615M | $30.7M |
| Broad 109 buildings — every office building >$20M citywide, ~$86M avg., $9.4B total assessed | $1.37B | $68.4M |
| Widest 237 buildings — every office building >$5M citywide, ~$45M avg., $10.7B total assessed | $1.56B | $78.0M |
Source: Philadelphia OPA (opa_properties_public), all parcels coded as a dedicated office building type, pulled 2026-09-28. Cost figures use the same "actual proposal" (flat 100%-off improvements, no phase-in; land stays taxable, about 20% of assessed value) formula as the calculator above, with units/unit-value scaled to each pool's average building size. The narrow-pool figure is summed from the 42 buildings' OPA 2027 taxable values; the broad and widest rows scale one average building to each pool's size, so they are less precise.
The 42-building pool is the only one actually screened for vacancy and conversion viability (CoStar data: pool screened on Feb. 2026 data, occupancy and size refreshed Oct. 1, 2026). The 109- and 237-building citywide pools are not vacancy-screened — they're every large office building in the city by assessed value, occupied or not, and most of them are unlikely to convert because they're functioning, tenanted buildings with little reason to. These are ceiling estimates for "what if every eligible building converted and would otherwise have kept paying full office tax," not a forecast. The calculator above nets out what the city would have collected without conversion, which is the more realistic comparison. The table's figures are fixed and do not change with the calculator's settings. Real adoption will land well below the widest pool, plausibly close to or below the narrow one. All three assume every building takes the full 20-year exemption at once, spread evenly over 15 years — a faster or slower adoption pace changes the number, but not the 20-year total.
The explorer rates 42 of the 59 Center City buildings on the CCD list as strong or possible conversion candidates. They are paying tax now. This applies the calculator above to each building's actual taxable value today, at three levels of conversion. The map and building details are in the Building Explorer.
The 42 strong and possible candidates in the Building Explorer are the most likely conversion candidates anywhere in the city. Conversions exit the assessment-appeal spiral permanently by replacing a volatile, BRT-vulnerable commercial assessment with a stable residential one. They also tighten the remaining office market — removing vacant SF from inventory supports assessments for buildings that stay office and makes future appeals harder to win.
Exits the assessment-appeal spiral permanently. Residential assessments don't track office vacancy cycles.
Removes vacant SF from inventory, supporting citywide assessments and making future BRT appeals harder to win.
Before arguing for a new 20-year abatement, it's worth being straight about what's known about the existing 10-year one — including the parts that complicate a simple "it works" story. Three sources cover this ground. Two of them are more supportive; one is pointedly critical. All three are worth reading, not just the convenient one.
The Finance Department commissioned Jones Lang LaSalle to model what happens to development, jobs, and revenue under different abatement designs (an update to JLL's 2014 study). Its bottom line: eliminating the abatement entirely would cut the pace of development by 40–50% and cost 1,700–1,900 construction jobs, while adding only about $7.8M to the School District over five years — every modeled alternative to the status quo came at some cost to development, jobs, or revenue. The "crossover point" (where School District revenue under the abatement catches up to a no-abatement scenario) lengthened from 15–18 years in 2014 to 18–22 years in 2018. As of 2017, only about 3% of parcels citywide (15,359 of ~580,000) had an active abatement. Read this as City-commissioned and favorable to keeping the program — it was written to evaluate policy options for the administration that commissioned it, not as a neutral third party.
A working paper comparing Philadelphia's outcomes to Camden, NJ — a similarly distressed city without a comparable abatement — over roughly two decades. Finds the 2000 abatement "materially increased marginal construction, contributed to reductions in vacancy and blight," and was "associated with renewed population growth," and argues it strengthened the city's long-run fiscal position by converting non-taxpaying blighted parcels into durable taxpaying ones. AEI is a right-leaning think tank and this paper reads as advocacy for place-based tax incentives generally, not a neutral evaluation — treat its Camden comparison as one methodology among several, not settled fact.
An independent watchdog-office analysis that asks a different question than JLL's: not "does this pay for itself," but "who actually captures the benefit." Its findings are pointed: the abatement conferred $1.05 billion in cumulative tax benefit since 2000 (~$93M in 2017 alone), but just 10 of Philadelphia's 158 neighborhoods captured 59% of that benefit — led by Rittenhouse, Northern Liberties, Logan Square, Washington Square, and Graduate Hospital — and within abated properties, the wealthiest 7% (valued above $700K) captured 51% of the total benefit. The median abated property assessed at $202/sq ft, 93% higher than the citywide median of $105/sq ft. This isn't a direct rebuttal of JLL's jobs/development numbers — the two reports are answering different questions — but it's a real finding that the existing abatement's benefits have been heavily concentrated in already-wealthy, already-booming neighborhoods, and any honest case for a new abatement needs to reckon with that, not skip past it.
A program can simultaneously "pay for itself in the long run" and be "distributionally regressive in the near term" — these aren't contradictory findings, but they point toward different design choices. It's part of why this page leads with the actual proposal's real net cost rather than a rosier hypothetical, and why the 20-year proposal's geographic concentration (29 of the 42 strong and possible candidates in a single district) is worth watching against the same pattern the Controller found in the existing program.
Built entirely from Philadelphia's public parcel-assessment history — no internal city data, no assumptions beyond what's stated here.
Office erosion figures are sourced from Philadelphia OPA via OpenDataPhilly, 46 matched CCD commercial parcels tracked 2019–2026. The during-abatement evidence table is independently re-derived from the assessments table's land and non-exempt improvement values at each year's actual combined tax rate. The calculator's "actual proposal" scenario models a full 20-year, 100%-off exemption on the converted portion of a building; the "phased alternative" is a hypothetical 5%/yr, 20-year step-down, not what's currently drafted. Results are net property tax versus either doing nothing or the existing 10-year conversion abatement. The exemption design is a toggle: either only the increase over the pre-conversion assessment is exempt (as in Philadelphia's current abatements; the default view), or all improvements are exempt and only land is taxed. Which one applies depends on the bill text. All dollar figures are nominal (no discounting) at a constant 2025 tax rate (City 0.6159%, School District 0.7839%). The share of buildings that would otherwise have kept paying full office tax and the share of conversions that would have happened anyway are adjustable under "What would have happened anyway".
Combined City + School District real estate tax rate verified against Philadelphia's official rate schedule for every year in this window: 1.34% (2015), 1.3998% (2016–2027).