Welcome to the Real Estate Standards Organization (RESO) Data Dictionary Wiki

This wiki describes and organizes the terms and fields related to the transmission of real estate data. Please review the Introduction pages and familiarize yourself with the left-side navigation bar for items like Resources, Groups, Fields and Lookups.

Each item includes a definition, attributes and points of integration. See Terms and Definitions for additional meanings of terms within a page.

If you want to be part of the real estate data conversation, please join our growing ranks as a RESO member. Membership includes free certification. | Join RESO

DD 1.7 Approved: December 18, 2018.

DD 2.0 Approved: October 23, 2023.

Official Data Dictionary Wikis

Data Dictionary 2.0 Wiki | Spreadsheet

Data Dictionary 1.7 Wiki | Spreadsheet

Data Dictionary 1.6 Wiki

Data Dictionary 1.5 Wiki

Other Downloads

Important for Certification

Data Dictionary 1.7 remains the most current version for RESO certification testing purposes. Data Dictionary 2.0 testing is right around the corner and is expected to begin in full in 2024. 

Ratified standards can be found on RESO's GitHub.

Certification testing specifications and change proposals are posted at transport.reso.org. | RESO Data Dictionary Endorsement | RESO Certification | RESO Commander (Client tools and libraries to work with and test RESO Web APIs.)

Members Only: Specifications and worksheets can be found on the RESO Data Dictionary Workgroup home page, along with a rich collection of content and discussions related to the Data Dictionary.

Mobile Users

The Data Dictionary Wiki is built upon Confluence, a web-based wiki. It is searchable within the Confluence app but switching to the desktop version while using Chrome, Safari, Firefox and other mobile browsers will offer wider visibility of the left-side navigation pane.


The RESO Data Dictionary was the result of a collaborative effort among numerous industry experts who volunteered their time, insight and expertise to the project. | Contributors

Page Revision Date: November 8, 2023