Mass Appraisal

The single largest real estate appraisal discipline that affects more property owners than any other is ad valorem mass appraisal. It is an appraisal practice with a unique intended use that can be defined as follows*:  the process of valuing a universe of properties as of a given date using standard methodology, employing common data, and allowing for statistical testing. 

*according to the Uniform Standards of Professional Appraisal Practice



ACT employs many people and processes in the mass appraisal pursuit of Market Value for all properties in our clients’ jurisdictions.

To achieve standard methodology

  • Appraisers are highly trained and kept up to date with continuing education.
  • Valuation Specialists are in regular communication with each other to ensure equitable valuation.
  • Reappraisal Managers maintain a “hands on” approach to each project.


To maintain common data

  • Appraisers are in the field daily verifying existing property data and gathering new data.
  • When available, aerial photography is utilized to enhance accuracy.
  • Data Entry Managers and staff work diligently to ensure that data returned from the field is accurately recorded for each property.


To allow for statistical testing

  • All data is stored in a custom Computer Assisted Mass Appraisal (CAMA) system designed specifically for our purposes.
  • Data is regularly standardized using edits in the CAMA system to look for irregularities.
  • State required statistical tests are built right into the custom CAMA system, in addition to more detailed tests used by our appraisers and managers.


ACT is committed to providing our clients with a staff consisting of the most educated, experienced and qualified real estate valuation specialists, making available a level of expertise and professionalism never before offered in the mass appraisal business.