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CAQH CORE Connectivity establishes key connectivity, security and authentication requirements including acknowledgements, error handling, and the CAQH CORE Connectivity “Safe Harbor” creating a national connectivity mechanism that trading partners can be assured will be supported when healthcare information is exchanged.

As the healthcare industry continues to progress toward achieving alignment and interoperability across systems and technologies, updating common methods of connectivity and enhancing security is necessary to ensure requirements continue to meet industry need.


Current and Past Versions of CAQH CORE Connectivity


All CAQH CORE Infrastructure Operating Rules require the use of the most current CAQH CORE published and adopted version of the CAQH CORE Connectivity Rule. The most recent published and adopted version of CORE Connectivity: CAQH CORE Connectivity Rule vC4.0.0.


As organizations may be on varying implementation timelines in efforts to migrate to the most current published version of CAQH CORE Connectivity, the table below references all past and current CAQH CORE Connectivity Rules and associated technical documents. Entities seeking CORE Certification are required at a minimum to implement the version of CORE Connectivity published two years prior from when pursuing certification testing.


Implementers of the HIPAA mandated CAQH CORE Operating Rules are also required to maintain support for CORE Connectivity versions as noted in the table below.


For additional information about implementing CAQH CORE Connectivity, please contact the CAQH CORE Certification team at


For more information about federally mandated operating rules, please click here

CAQH CORE Connectivity Rule



CAQH CORE-Required Processing Mode Payload Type Tables

Original Publication Date


CAQH CORE Connectivity Rule vC4.0.0

XML Schema vC4.0.0 

WSDL Schema vC4.0.0 

CAQH CORE-Required Processing Mode Payload Type Tables vC4.0.0

December 2020


CAQH CORE Connectivity Rule vC3.1.0

XML Schema vC3.1.0 

WSDL Schema vC3.1.0 

CAQH CORE-Required Processing Mode Payload Type Tables vC3.1.0

September 2015


CAQH CORE Connectivity vC2.2.0*

XML Schema vC2.2.0

WSDL Schema vC2.2.0


July 2008

Required to be supported under Affordable Care Act (ACA)-mandated Operating Rules for eligibility & benefits, claim status, and ERA transactions.

CAQH CORE Connectivity vC1.1.0*




July 2008

Required to be supported under Affordable Care Act (ACA)-mandated Operating Rules for eligibility & benefits transactions.

*In 2020, CAQH CORE implemented a New Operating Rule Structure to transition the CAQH CORE Operating Rules from phase-based rule sets to rule sets based on business transactions.