2026 taxable assessment $320,800 × 1.3998%. Estimate—not a bill or account balance.
OPA also publishes a 2027 assessment of $424,200; it is not the 2026 billed-year value.
House report
527 Mifflin St
6 bd · 2 ba · 3 stories · 2,196 sqft · RSA5 · built 1915
Owner-occupancy signal · assessed $421K (2026) · 2027 OPA assessment $424K · sold 1×. On the 500 block of Mifflin St.
BlockReport AI · cited public records
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Property summary
Assessment$420,8002026 OPA assessment · 2027: $424,200
Last sale$305KRecorded 2019
Est. tax bill$4,491/year2026 OPA · Homestead-adjusted
Tax delinquencyNo 2022 matchNot proof account is current
Permits7Every fetched City permit
Violations0 openNo historical match in fetched records
“Open” reflects records available then historical records keep their source dates estimates are labeled
Question or correct this record
BlockReport can explain a discrepancy, but it cannot rewrite an official City record. Use the agency that owns the underlying fact:
Property tax
The estimate, live balance, and back-tax record are different.
BlockReport can calculate the annual tax from the City’s taxable assessment. Payments, credits, interest, and a current amount due live separately in Philadelphia Tax Center.
A Tax Center balance is net of bills, payments, credits, interest, and adjustments. A credit—or an amount due—is not automatically “back taxes.”
OPA 0114154002026 OPA removes $100,000 from the taxable assessment through the owner-occupant exemption.
Historical delinquency sources No current conclusion
This parcel did not match the June 2022 delinquency snapshot. That absence does not confirm the account is current today.
For a purchase, refinance, or closing, request the City’s official Property Payoff statement in Tax Center under “More options.”
What stands out
From the public recordNew construction
Record summarynew construction appears in a 2009 permit, followed by a recorded transfer of $305K in 2019.
View supporting records →What to do with this
The record, translated into moves — what a buyer, the owner, and a landlord would each want to check next under Philadelphia's actual rules.
If you’re buying
Built 1915: lead rules apply
Federal law requires a lead-paint disclosure at sale for any pre-1978 home. If it will be rented, Philadelphia also requires a lead-safe or lead-free certificate before a rental license can issue.
Zoned RSA5: one household by right
Single-family rowhouse (the classic Philly row). Converting to a duplex or apartments needs a use variance the zoning board rarely grants — Pennsylvania courts require a physical hardship of the lot itself, and economics alone do not qualify.
Derived from the fetched property records and linked City guidance as of 2026. Assessment treatment is not a substitute for an exemption approval, live balance, title report, license, occupancy certificate, or inspection. Informational only — not legal, tax, or investment advice.
Assessment and tax history
Every fetched annual City assessment for this house, compared with its block and ZIP. The figures show assessment change, the billed-year tax estimate, dated tax records, and recorded transfers. They do not estimate market appreciation or investment return.
Assessed value
$420,800
2026 billed-year assessment · 2027: $424,200 · built 1915
Price / sq ft
$193
block $224 · below block
Assessment change
+73%
+5%/yr since 2016 · 2027 +1% vs 2026
Est. tax bill / yr
$4,491
1.07% effective
Jun 2022 tax snapshot
No match
not proof the account is current
Times sold
1
Assessment vs. the block and ZIP · every dated City record marked on the line
- OPA assessment · 2016$246K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- OPA assessment · 2017$246K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- OPA assessment · 2018$246K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- OPA assessment · 2019$243K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- OPA assessment · 2020$263K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- OPA assessment · 2021$263K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- OPA assessment · 2022$263K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- OPA assessment · 2023$350K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- OPA assessment · 2024$350K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- OPA assessment · 2025$421K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- OPA assessment · 2026$421K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- OPA assessment · 2027$424K assessed valueOPA’s value on the City tax roll for that year. It is not an appraisal, listing price, sale price, or live tax balance.How Philadelphia property assessments work ↗
- Deed / sale · 2019Deed / sale $305KA recorded real-estate document or transfer event. The amount and date can be useful history, but the underlying deed and transfer-tax filing control the parties, consideration, and legal effect.How to read the recorded document ↗
- Permit · 2009-07-16New ConstructionThis permit category usually covers construction, repair, alteration, addition, or occupancy work. The approved scope—not the short category—defines what was authorized, and issuance alone does not prove completion.Philadelphia construction and repair permits ↗
- Permit · 2019-05-06Interior Non-Load-Bearing Wall Demo.This permit category usually covers construction, repair, alteration, addition, or occupancy work. The approved scope—not the short category—defines what was authorized, and issuance alone does not prove completion.Philadelphia construction and repair permits ↗
- Permit · 2019-06-18AlterationsThis permit category usually covers construction, repair, alteration, addition, or occupancy work. The approved scope—not the short category—defines what was authorized, and issuance alone does not prove completion.Philadelphia construction and repair permits ↗
- Permit · 2019-07-02New ConstructionThis permit category usually covers construction, repair, alteration, addition, or occupancy work. The approved scope—not the short category—defines what was authorized, and issuance alone does not prove completion.Philadelphia construction and repair permits ↗
- Permit · 2023-07-06Addition and/or AlterationThis permit category usually covers construction, repair, alteration, addition, or occupancy work. The approved scope—not the short category—defines what was authorized, and issuance alone does not prove completion.Philadelphia construction and repair permits ↗
- Permit · 2023-07-07AlterationsThis permit category usually covers construction, repair, alteration, addition, or occupancy work. The approved scope—not the short category—defines what was authorized, and issuance alone does not prove completion.Philadelphia construction and repair permits ↗
- Inspection · 2011-07-19HCEU INSP (Housing Code Enforcement Unit inspection)A legacy L&I inspection label. The unit inspected housing for property-maintenance, fire-prevention, and related code compliance; the separate status says how that visit ended.What Philadelphia inspections check ↗
Property assessmentBlock median & rangeZIP 19148 medianAssessmentDeed / salePermitInspection
Scroll horizontally to move through the years. Each icon sits on its recorded date; records without a day are labeled and centered within their year. Select one to explain the filing.
Highlight
Every dated record8 events · exact dates, newest first
- PermitAlterations
- PermitAddition and/or Alteration
- PermitNew Construction
- PermitAlterations
- PermitInterior Non-Load-Bearing Wall Demo.
- Deed / saleDeed / sale $305K
- InspectionHCEU INSP (Housing Code Enforcement Unit inspection)
- PermitNew Construction
The paper trail
New constructionnew construction appears in a 2009 permit, followed by a recorded transfer of $305K in 2019.
- 2009 New ConstructionPermit
- 2011 Inspection passedL&I visit
- 2019 $305KTransferInterior Non-Load-Bearing Wall Demo.PermitAlterationsPermitNew ConstructionPermit
- 2023 Addition and/or AlterationPermitAddition and/or AlterationPermitAlterationsPermit
Records behind the chart
Browse the source ledger
The chart above is the primary timeline. This drawer preserves every underlying dated row and its filed status for source-level review.
Browse 9 dated records deeds, permits, inspections, licenses, violations, certifications & appeals
- PermitAlterations
Permit PP-2023-009276 · Completed
RELOCATE KITCHEN SINK DRAIN REPLACE 1ST FL TOILET AND VANITY
- PermitAddition and/or Alteration
Permit EP-2023-006265 · Completed
Install new kitchen wiring: 5 new 20 amp / 120 volt / AFCI / GFCI circuits 1 new 15 amp AFCI circuit for lighting wiring for dishwasher, disposal and microwave 10 new receptacles 8 new luminaires as per 2017 nec
- PermitAddition and/or Alteration
Permit RP-2023-006592 · Completed
EZ PERMIT STANDARDS ALTERATIONS For alterations to an existing one family dwelling as per attached standard. Deviations from this standard will result in permit revocation and require submission of construction plans. Structural alteration or repair is expressly prohibited under this permit. Prohibited structural work includes any modification to exterior walls, party walls, floor/roof framing or foundations, underpinning and excavations (i.e., digging in basement). Any work/alterations to the basement/cellar are expressly prohibited unless documented as an existing habitable space with heights and means of egress per conditions of the EZ standard. separate permits required for mechanical, electric and plumbing, etc. *No basement alterations of any kind were proposed or approved for this permit* *No structural alterations of any kind were proposed or approved for this permit* KITCHEN 10x12 Remove and replace GWB from walls and ceiling
- PermitNew Construction
Permit 990421 · Completed
WIRING & INSTALLATION OF DEVICES, RECESSED LIGHTING IN BEDROOM & BATHROOM, PER 2014 NEC
- PermitAlterations
Permit 985878 · Completed
NEW STACK,WASTE AND WATER LINES FROM BATHROOM TO NEW 3RD FLOOR BATHROOM WITH 1-WATER CLOSET,1-LAV AND 1-TUB.THE INSTALLATION WILL COMPLY WITH THE PHILADELPHIA PLUMBING CODE 2004.
- PermitInterior Non-Load-Bearing Wall Demo.
Permit 973629 · Completed
REHAB 3RD FLOOR ONLY ALSO ADDING A BATHROOM***STRUCTURAL ALTERATION OR REPAIR IS EXPRESSLY PROHIBITED UNDER THIS PERMIT. PROHIBITED STRUCTURAL WORK INCLUDES ANY MODIFICATION TO EXTERIOR WALLS, PARTY WALLS, FLOOR/ROOF FRAMING OR FOUNDATIONS; UNDERPINNING AND EXCAVATIONS (I.E. DIGGING IN BASEMENT***WORK BEING DONE BY HOMEOWNER***
- Recorded transfer$305K transfer
2019
- InvestigationHCEU INSP (Housing Code Enforcement Unit inspection)
Case 287591 · PASSED
A legacy L&I inspection label. The unit inspected housing for property-maintenance, fire-prevention, and related code compliance; the separate status says how that visit ended. The cited inspection visit was marked passed.
- PermitNew Construction
Permit 226188 · Completed
REMOVE OLD SERVICE PANEL, REPLACE WITH NEW. EXISTING SERVICE OF 100 AMPS-ADD GROUND ROD...... IN ACCORDANCE WITH 2005 NEC
What this record suggests
The City file documents 7 permits touching kitchen work, bathroom work, electrical work, plumbing. 7 carries a completed, issued, or approved status; that documents the filing, not the present quality of the work.
Informational only — not investment advice or a consumer report (FCRA).
The property, on paper
The city assessor's field record — the physical spec sheet behind the assessed number.
Bedrooms
6
Bathrooms
2
Stories
3
Interior
2,196 sqft
livable area
Lot
1,088 sqft
Basement
Full
city code D
Heat
Undetermined
city code H
Central air
No
Exterior condition
Average
city code 4
Above averageBelow average
Interior condition
Average
city code 4
Above averageBelow average
Quality grade
B-
assessor's grade
ABCDE
Zoning
RSA5
city zoning code
OPA field-assessment attributes. Condition and grade are the assessor's codes, not an inspection.
Run the numbers
What owning 527 Mifflin St takes, at your price and your rate. Taxes start with an annual estimate from the City’s taxable assessment, not a current bill or balance; rent starts at the area median. Assessed value is not an asking price — set the price slider to the real one.
When this house last sold (2019) a 30-year mortgage ran about 3.94% — Freddie Mac's average that year.
Mortgage
—
P&I · 30-yr fixed
All-in monthly
—
+ taxes & insurance
Estimated cash needed
—
down + 4% planning allowance
Modeled cash flow
—
rent − shown costs · /mo
Modeled cap rate
—
modeled NOI ÷ price
Modeled cash-on-cash
—
modeled year-1 return
Scenario for orientation, not advice. Assumes a 30-year fixed loan, $1,400/yr insurance, 1% of price/yr maintenance, and buyer cash equal to the down payment plus 4%. Taxes use this parcel's taxable assessment, not a live Tax Center balance. Cash flow and returns exclude vacancy, management, utilities, HOA or condo fees, leasing costs, income tax, and unplanned capital work.
Block context
527 Mifflin St sits on the 500 block of Mifflin St. Open the block report to compare its parcels, ownership and public-record history.
See the whole block →Next door: 525 Mifflin St · 529 Mifflin St
Where this comes from
- Assessment, spec sheet & owner — OPA Property Assessments, Office of Property Assessment
- Sales & deed history — Realty Transfer Tax records, Recorder of Deeds
- Permits, violations & inspections — L&I Property History · Atlas
- Tax delinquency snapshot · June 2022 — Real Estate Tax Delinquencies, Dept. of Revenue
- Historical tax ledger & liens · through 2016 — Real Estate Tax Balances, Dept. of Revenue
- Current property-tax balance — Verify with Philadelphia Revenue
- Zoning appeals — L&I & Zoning Board appeals
- Neighborhood income & rents — US Census ACS 5-year estimates
- Historical mortgage rates — Freddie Mac Primary Mortgage Market Survey, annual averages
- Imagery — Street photo © Google · Aerial © Esri, Maxar
Methodology & freshness
This report was assembled Jul 11, 2026, 1:37 AM ET. Available City datasets are queried from OpenDataPhilly (phl.carto.com) and the cited City ArcGIS feeds; record queries paginate rather than silently taking a first page. For this property: Permits: queried · Violations: queried · Investigations: queried · Appeals: queried · Licenses: queried · Building certifications: queried. “Unavailable” means the source query failed or was not supplied, not “no record.” Reports re-pull on view after seven days and on an overnight rolling schedule; citywide benchmarks recompute weekly. Source dates still govern: the parcel-level tax-delinquency snapshot is June 2022 and the separate detailed tax ledger ends in 2016, so neither establishes today’s balance. The live balance and date-effective payoff must be verified in Tax Center. AI-written passages are grounded in the assembled record and rejected if they state a number the record does not hold.
Official city record ↗ · L&I history ↗ · See the whole block · Download this record (JSON)