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RESO certifies systems that comply with real estate data standards. Certification ensures interoperability between technology systems that speak a common language. Standards provide that common language.

RESO Map of Certified Organizations

RESO Certifies Web API: MLSs Are Retiring RETS


The Certification Process

RESO’s certification process is now highly automated. It is primarily processed between RESO and the technical vendor.

  1. Compliance Testing: RESO uses access credentials supplied by the applicant’s technology vendor and verifies standards conformance for the system.
  2. Certification: Applicants whose systems pass testing are asked to confirm results and provided with certificates from RESO.

Rather than initiating your own certification as you did in the past, please talk to your technology provider about getting certified with RESO. They will work directly with RESO staff to get you started and we will notify you once your system has completed testing and is ready to certify.

Coming Q4 2021: In-Depth Certification Reports

RESO certifications were traditionally a pass-fail proposition. Today, RESO is publishing in-depth reports on the metadata, standard fields and custom local fields of certified systems.

MLS Certification Dashboard

Individual MLS Certification Reporting on Resources, Fields, and Lookups

Comparisons of Data Advertised in Metadata, Available in Payloads, and Averages

Individual Fields and Lookup Reports

Web API Server Performance Statistics and Comparisons

These reports will be available here on in Q4 of 2021. Please join the RESO Transport and Certification Workgroup sessions to learn more.

Certification Quick Facts

  • RESO is currently certifying on Web API Core 2.0.0 and Data Dictionary 1.7.
  • Certifications on the two most recent versions of a standard are viewed as active certifications by RESO.
    • Certification on the most recent standard is classified as “Certified Current.”
    • Certification on the previous most recent standard is classified as “Certified Legacy.”
  • The National Association of REALTORS® requires REALTOR®-owned and operated MLSs to be in compliance with the most recent RESO standards (i.e., Certified Current, within 12 months of RESO ratification).
  • Certification isn’t just for MLSs. Brokers and technology vendors with Web API servers are also certifying with RESO.

Full Details on Certification by Organization Type

RESO Certified Organizations