This report examines how modern, open-source assessment methods could be used to produce fair, transparent, and affordable countywide reassessments.
Using publicly available data and open-source valuation models, we estimate updated assessments for residential properties across Allegheny County, evaluate their quality against International Association of Assessing Officers (IAAO) standards, and estimate the cost of implementing a regular reassessment program.
Among our findings:
Modern automated valuation methods can produce assessments substantially closer to market value than the current system using publicly available data.
The largest relative assessment increases are likely to occur in neighborhoods that have appreciated rapidly over the past decade, particularly within the City of Pittsburgh.
Existing land assessments often value neighboring parcels very differently despite having nearly identical locations and characteristics, reducing confidence in the fairness of the system.
Regular reassessments could likely be performed in-house by Allegheny County for approximately $1 million per year, far below the costs often associated with court-ordered reassessments.
Based on estimates from the economics literature, regular reassessments could generate tens of millions of dollars in annual economic benefits by improving efficiency, reducing distortions, and increasing confidence in the property tax system.
The report also introduces an open-source methodology for estimating both total property values and land values, documents limitations in the County's existing datasets, and demonstrates how greater transparency can improve public confidence in the assessment process.
In addition to the report, we've released an online HomeAssessment Explorer that allows residents to view our estimated assessments and how they will likely impact their taxes.Our goal is not to produce Allegheny County's official reassessment. Rather, it is to demonstrate that modern reassessment is technically feasible, affordable, and should be conducted using transparent methods and open data.
We hope this report contributes to the ongoing discussion surrounding Bill 13892-26 and helps move Allegheny County toward regular, fair, and transparent reassessments.
We welcome and encourage any and all feedback on our work.