Ex Parte Explained: The Mechanics of Medicaid Eligibility Automation

Under federal requirements (42 CFR 435.916), Medicaid agencies must attempt to determine a member’s eligibility without requiring action from the individual – a process known as ex parte. The requirement has been a part of Medicaid eligibility policy for over a decade, though it has expanded in recent years, including in H.R. 1: The One Big Beautiful Bill Act (OBBBA). Policymakers have pointed to potential operational benefits of ex parte, including reducing administrative work for Medicaid agencies and Medicaid members, and increasing the accuracy of Medicaid eligibility determinations.

The origins of modern ex parte

The current framework was established in 2012 under a federal rule implementing the Affordable Care Act (ACA) for eligibility changes that required states to use available and trusted data before asking members for information at renewal.  The ACA also drove the creation of the Federal Data Services Hub, which launched in October 2013 and gave states a single connection point to federal data sources – like IRS income and Social Security Records – that had previously required separate data and security agreements to access.

States comply with these federal requirements by:

• Using reliable data sources: Per federal regulation, states must gather information that CMS considers to be ‘reliable information’ for use in the ex parte process. This includes information from the member’s account and from other data sources that are available to the state. States may draw on a variety of data sources, including existing case records, state data sources (wage or tax records), or federal data sources like the Federal Data Services Hub or the open-source Eligibility Made Easy (Emmy) tool.
• Creating processes around manual and automated eligibility actions: Ex parte can be completed through automated system logic, manual caseworker review, or a combination of both.

In the years that followed passage of the ACA, states focused on building new eligibility systems and gradually ramped up implementation of the ex parte requirement. As of January 2020, there was wide variation in states’ ex parte rates.

Ex parte took on increased prominence during the unwinding of the COVID-19 Public Health Emergency (PHE) continuous coverage requirement. Starting in April 2023, states had to redetermine eligibility for all enrollees for the first time in over three years. At the start of unwinding, the national ex parte rate was approximately 30 percent. Through investment in data connections and system automation, the national average rose to over 55 percent by the end of the unwinding period. These efforts have helped modernize application and renewal processes by moving away from more manual processes.

Congress elected to build on the use of ex parte processes in H.R. 1, the One Big Beautiful Bill Act (OBBBA). The law requires states to use ex parte for verifying compliance with, or exclusions from, work and community engagement requirements before requiring an individual to provide information. OBBBA also increases the frequency of renewals for the expansion population from once every 12 months to once every 6 months, meaning states will run ex parte twice as often for this group. This means that as states implement work and community engagement requirements, they are focused on expanding and modernizing data sources for ex parte verification.

What are the steps in the ex parte process?

While implementing the ex parte process can be complicated, the outlined steps as identified in the November 2024 CMCS Information Bulletin provide guidance to Medicaid agencies:

• Identify members that need to have their eligibility determined
• Gather whatever information is already available. This information should be based on reliable data such as existing case records, state data sources, or federal sources like the Federal Data Services Hub.
• Determine whether the person qualifies using that information through automated logic, manual review, or both.
• Communicate the outcome:
  • If eligibility is confirmed, the member receives a notice that their application is approved or their coverage is renewed.
  • If more information is needed, the member receives a request for additional information or a renewal form to complete.

The common idea is that states use information that the state already has to simplify steps for Medicaid members and state staff. If a state can’t determine if a member is eligible, it asks for more information from the member and incorporates that information into the case file. State staff can then determine based on that additional information if someone is eligible for continued coverage.

What are some of the data sources states use for ex parte renewals?

Ex parte renewal processes are dependent on the data available to the state. States draw on a combination of state, federal, and commercial data sources when attempting to verify a member’s eligibility without requiring information from the individual.

The Federal Data Services Hub is the primary federal infrastructure supporting this process. Built as a part of the ACA implementation and operational since October 2013, to coincide with the launch of the marketplaces, the Hub provides Medicaid agencies with a single connection point to multiple federal data sources that had previously required separate connections and data sharing agreements.

While data sources are continually being added, Medicaid agencies have historically been able to use the Hub to leverage reliable data from organizations such as: Social Security Administration for Social Security Number Verification, Department of Homeland Security for Citizenship verification, and CMS for Medicare enrollment and other coverage. The Hub also connects to commercial sources like the Verify Current Income function, which can provide employment and income verification based on payroll records contributed by employers. Medicaid agencies must pay to leverage these commercial data sources. As state use of the Hub grew, CMS reported a sevenfold increase and transitioned the function to a Medicaid-claimable service at the 75/25 match beginning July 1, 2024.

While the Hub covers many verification needs, its existing data sources are not sufficient to verify compliance with – or exemptions from – the new work and community engagement requirements. In 2026, CMS launched new open-source solutions including Eligibility Made Easy (Emmy), an open-source tool designed to fill these gaps. Emmy supports consent-based income verification, and the ability for members to upload documents supporting volunteer activity. In the June 2026 Interim Final Rule implementing the work and community engagement requirements, CMS also indicated that they are exploring pulling additional data sources, like National Student Clearinghouse and U.S. Department of Veterans Affairs data, into the Hub.

States supplement the Hub and Emmy with their own data sources. State wage and earnings records are among the most used data connections for verifying income at renewal. Some States have also enhanced the accuracy of their ex parte renewals by drawing on SNAP and TANF program data, Department of Corrections records, vital statistics, asset verification systems for non-MAGI populations, and in some cases newer sources like U.S. Postal Service change of address or state lottery and gaming records to flag changes in circumstances.

How ex parte works in practice: an income verification example

Consider a working parent enrolled in Medicaid whose renewal is approaching. The state system flags the case 60 to 90 days before the eligibility period ends and begins the ex parte process by pulling information already in the member’s case, then querying available data sources such as state wage records, the Federal Data Services Hub, and commercial data sources.

• State wages and earnings data is often checked first. States already have it through quarterly employer reporting. However, data can be several months old by the time it is used and can often miss self-employment or gig work.
• The Federal Data Services Hub is often checked next. It provides a broader view through IRS tax data and SSA benefit information, which can include self-employment reported on taxes. However, IRS data reflects the most recent tax filing, which can be older than state wage and earning data.
• Commercial sources may be checked last. Payroll data updates with each pay period, making it the most current source available. However, it only covers W-2 employees at contributing employers and involves significant costs for states.

If the Medicaid agency cannot complete the renewal via ex parte, either because adequate data is not returned or because the returned data indicates that the individual may not be eligible for Medicaid, the Medicaid agency must send the individual a renewal form that the individual must complete.

Operational impacts of automated ex parte renewals

Over the past several years, state and federal policymakers have expanded the use of automated ex parte. This has been driven by federal law, an increased focus on system modernization, and a desire to simplify eligibility processes for state caseworkers and individuals served by the program.

Policymakers have pointed to three potential operational benefits of ex parte renewals:

• Reduced administrative work for Medicaid agencies. Because automated ex parte renewals occur without caseworker intervention, they reduce the volume of paper renewals, phone contacts, and caseworker touchpoints required to process cases. This can save Medicaid agencies on administrative costs by reducing the number of eligibility workers needed to process applications and renewals. It also allows Medicaid eligibility workers to focus on more complex cases, such as evaluating eligibility for Home and Community Based Services (HCBS) waivers.
• Reduced administrative work for Medicaid members. Because ex parte renewals require states to check existing data sources before requesting information from members, they reduce administrative work for Medicaid members. They can also reduce the rate of procedural terminations – cases where individuals lose coverage not because they are ineligible, but because they did not respond to a renewal request or return required documentation.
• Reduced potential for human error. Ex parte processes draw on data sources – such as wage records, tax data, and the Federal Data Services Hub – rather than relying solely on member-submitted documentation. This may reduce the potential for human error by limiting opportunities for inaccurate self-reporting and manual data entry; however, research is needed to confirm if this increases the accuracy of eligibility processes.

Because automated ex parte renewals occur without caseworker intervention, they are dependent on strong data infrastructure. This includes timely access to complete and current data, along with accurate systems instructions that review data sources in accordance with the state or territory verification of business rules. Medicaid agencies must also have strategies for auditing their ex parte processes, to ensure that their systems are adjudicating cases in line with state/territory and federal eligibility policy. The relationship between automated ex parte processes and the accuracy of eligibility determinations is an area where more research is needed.

Ex parte and the road ahead

Over the coming years, ex parte processes will continue to be a focus area for Medicaid agencies. OBBBA introduces changes to Medicaid eligibility policy, including work and community engagement requirements for low-income adults who do not have dependent children or certain disabilities (i.e., the expansion group), along with more frequent redeterminations for this same enrollment group. States are focused on ex parte processes as they implement these policy changes.

In OBBBA, Congress explicitly requires states to use available data sources to attempt to verify if an individual meets the work and community engagement requirements – or falls under an exemption or exclusion – before requesting information from the individual.

States will be able to use existing ex parte data sources to verify some forms of compliance and some exclusions. For example,

• States can use existing wage data sources to check if a member is making over 80 times the federal minimum wage each month.
• States may be able to use existing data sources, including Medicaid provider payments and encounter data to identify individuals that may meet the “medical frailty” exclusion.
• States can use data they collect on their application forms – like if an applicant is pregnant or postpartum, used to be in foster care, or is an American Indian – to verify certain exemptions and exclusions.

The data structure to support ex parte verification for some activities (such as volunteering or enrollment in an educational program) and some exclusions (such as veterans with 100% rated disability) may not yet exist in some states. States are focused on identifying and linking to these data sources as they implement work and community engagement requirements. CMS has also developed new tools, such as the open-source Emmy tool, to support connections to verifiable data sources.

These changes arrive alongside an increase in renewal frequency: starting January 2027, renewals for the expansion population will move from once every 12 months to once every 6 months. CMS confirmed in a March 6, 2026 State Medicaid Director letter that states must still attempt ex parte verification before contacting a member at every renewal. This means that states will run ex parte twice as often for this population. Medicaid agencies are focused on operational improvements like robust data connections, accurate system logic, and regular reporting on ex parte processes to manage this increased volume of renewals.

Conclusion

Ex parte is a federal requirement that requires Medicaid agencies to check available data sources during Medicaid eligibility processes. Over the past decade, states have invested significantly in building the data connections, and automated eligibility logic to meet new federal requirements while reducing administrative work for both states and the people they serve.

Medicaid agencies will remain focused on ex parte processes as they work to implement new eligibility policies. OBBBA expands the scope of what ex parte must verify, introduces new data sources that states are building connections to, and doubles the renewal frequency for the expansion population. Meeting these demands will require robust, timely data infrastructure leveraging both federal and state data sources, well-documented system logic, and the ability to monitor and audit what automation is doing in real time.

This brief was written in partnership with the Tech Talent Project, which partners with the National Association of Medicaid Directors to surface promising practices and real-world examples from states and territories so Medicaid programs nationwide can advance locally tailored solutions and technical capacity advancements that deliver value for the people they serve and taxpayers alike. To learn more about how Tech Talent Partners with states please visit techtalentproject.org