MassGIS standard for digital parcels and related data sets

This standard for spatial accuracy and detail of assessor parcel mapping and related attribute information is for developing digital versions of assessor’s property maps for use in planning, property assessment, and map display.

Version 3, Released June 2022

Overview

This standard:

1. Provides communities a flexible specification for developing a digital parcel file suitable for use in a geographic information system (GIS). Because text labeling and the creation of a master address file are integral to extending the usefulness of a digital parcel file, portions of this standard address the creation of those datasets.
2. Makes it possible to merge digital property information from more than one community for multi-town mapping and spatial analysis.
3. Makes it possible to identify a single property parcel statewide based on a single unique identifier.
4. Provides various levels of documentation.
5. Assures a minimum level of spatial accuracy.

Version 3 of the standard replaces previous versions. However, it does not implement any new requirements. Nor does this version make changes that require modifying existing work processes or related software tools that automated compliance with Version 2.1 of this standard. The primary change in this version of the standard is that is easier to use and read. Previous versions of the standard had different levels: one, two, and three. All cities and towns now comply with “Level 3” of version 2.1 of the standard. Therefore, this version eliminates references to “levels” and is simply the Commonwealth’s standard for digital assessor parcel files. As defined in this standard, those files include both map and database files in an ESRI file geodatabase."

Please note that this standard is NOT a general purpose standard for traditional printed parcel map sheets. This standard for spatial accuracy and detail of property boundaries and related attribute information is for developing digital versions of assessor’s property maps for use in planning, property assessment, and graphic map display.  However, there is no intent to provide a standard for developing the authoritative definition of property boundaries or to specify limits for legal boundary determination or property conveyance purposes. Matters related to those more definitive interests remain the purview of the professional title attorney and/or professional land surveyor.

Document

MassGIS Parcel Data Quality Assurance - If you receive a data file from a contractor or develop one in-house and you want to have the file checked for conformance with  the MassGIS standard, contact send email to Craig Austin at MassGIS at [e-mail].  MassGIS provides this service at no charge to Massachusetts cities and towns.

Additional Resources

Full parcel standard (PDF)

View parcels with the Interactive Property Map