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Grove Hopper Research · July 2026

Philadelphia's 2027 reassessment, by the numbers: a modest median hides 30,000 homes with 20%+ jumps

Analysis of all 456,910 single-family properties in the city's official 2027 certified values · Source: Philadelphia Office of Property Assessment open data · Journalists: cite freely with a link.

+4.2%
citywide median increase
71.3%
of homes increased
1 in 5
homes rose 10% or more
~30k
homes rose 20% or more

The City of Philadelphia began mailing Tax Year 2027 assessment notices on June 30, 2026. The citywide story sounds mild: the median single-family home's market value rose 4.2% versus its 2026 value. But medians hide the tails — 21.2% of homes jumped at least 10%, and 6.5% (roughly 29,700 homes) jumped 20% or more. For a homeowner, a 20% assessment jump translates to roughly a 20% property-tax increase absent exemptions or a successful appeal.

The geographic pattern is the story: the hardest-hit zip code in Philadelphia is 19134 — Kensington, Harrowgate, and Port Richmond, among the city's lowest-income areas, where the median home's value rose 11.2% and more than 1 in 5 homes jumped 20% or more. Affluent Chestnut Hill (19118) ranks third. Rapid-appreciation, lower-income neighborhoods carrying the steepest increases is precisely the pattern assessment-equity researchers have documented in other cities.

The twelve hardest-hit zip codes

ZipAreaMedian 2027 increaseHomes up ≥20%Single-family homes
19134Kensington / Harrowgate / Port Richmond+11.2%21.8%19,593
19127Manayunk+10.8%8%2,500
19118Chestnut Hill+10.6%17.3%2,449
19128Roxborough+10.2%5.6%11,967
19115Bustleton+9.4%13.6%9,599
19142Elmwood / Southwest Philly+9.3%9%9,284
19116Somerton+9.2%2.7%8,516
19154Far Northeast+7.6%0.8%10,777
19114Torresdale+7.4%2.5%8,856
19136Holmesburg / Mayfair+7.1%5.9%9,618
19153Eastwick+6.4%13.7%3,528
19124Frankford / Juniata+6.1%3.5%18,738

What homeowners can do

Every Philadelphia owner has two review paths, both free to file: an informal First Level Review due September 1, 2026 (form included with the mailed notice) and a formal Board of Revision of Taxes appeal due October 5, 2026. Whether a jump is worth challenging depends on one question: does the new value exceed what comparable homes actually sold for? Our free checker answers that for any address in about two minutes, sources cited — and the Philadelphia appeal guide covers the process step by step. Homeowners should also confirm they have the Homestead Exemption, which shields $100,000 of assessed value.

Methodology

We queried Philadelphia's official open-data warehouse (phl.carto.com: assessments joined to opa_properties_public) on July 17, 2026, comparing certified 2027 market values against 2026 values for all single-family properties with a 2026 value above $50,000 — 456,910 parcels, the full population, not a sample. Percentages are shares of that population; zip rows shown have 2,000+ single-family homes. Queries available on request: hello@grovehopper.com.