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Encouraging Voter List Maintenance Efforts with an ERIC Indicator

EPI New Indicator Alert!

Every year, millions of Americans move, die, or experience one (or many!) of a full range of other life events, posing a real challenge to states as they try to keep their voter registration lists up to date. As a result of these comings and goings—normal for individuals, but often overwhelming in aggregate—1 in every 8 voter registration records is inaccurate. To combat this issue, a decade ago seven states (Colorado, Delaware, Maryland Nevada, Utah, Virginia, and Washington) joined forces to form the Electronic Registration Information Center, or ERIC, with assistance from the Pew Charitable Trusts.  Since then, the number of member states has more than quadrupled.

Membership in ERIC was added as an indicator to the Elections Performance Index in 2020.  ERIC has long been regarded as the gold standard of interstate cooperative arrangements in keeping voter registration rolls accurate in a way that honors the laws governing voter registration, encourages the registration of the unregistered, and protects vital personal information.  The EPI seeks to note and celebrate states that adopt best practices, which makes this new indicator an obvious one to add.

What is ERIC?

ERIC assists member states in improving the accuracy of their voter records by comparing registration lists to data from other governmental agencies, such as records from the DMV, the US Postal Service, and the Social Security Administration. Voter lists are compared across state lines as well; with the aid of ERIC, states can reach out to voters who have relocated to confirm their new address and encourage re-registration, or to confirm that a particular voter should no longer be on their rolls. ERIC is a state-run organization. The chief election official in each state appoints a member representative to serve on the Board of Directors , which oversees the organization. ERIC’s operating expenses are paid by the participating states themselves.

How ERIC works

Member states are accountable and financially responsible for the success of ERIC. States contribute financially by providing funds relative to the size of their population. States are provided with an in-state movers list, a cross-state movers list, a deaths list, and a duplicates list in order to keep the registration list accurate. Member states also make efforts to reach out to eligible-but-unregistered voters in order to expand the registration lists. States must comply with transparent documentation of all of their list-maintenance activities. Member states ensure the safe and secure transfer of the personal data that ERIC uses. In order to maintain anonymity within the ERIC system, the center employs a data privacy tactic called one-way hashing where confidential identifiers such as driver’s license numbers or last four digits of social security number are scrambled up in long strings of alphanumeric codes.


During the 2020 election, 30 states and the District of Columbia were members of ERIC. To integrate an “ERIC measure” into the Election Performance Index, we relied on a simple binary coding to indicate whether a state was a member of ERIC on Election Day. If a state is officially approved as an ERIC member before the election in question, the state gets included. 

In 2012, only seven states were ERIC members, but that number has grown steadily in each federal election year since: 

  • In 2014, 11 states plus DC were members 
  • In 2016, 19 states plus DC were members
  • In 2018, 23 states plus DC were members 

Since the 2020 election, one more state—Maine—has joined the organization, bringing the current total to 31 states and DC.


The image above shows a map of the United States indicating which states are ERIC member states and which states are not, as of the end of 2021.

Why add ERIC?

ERIC provides states with a well-organized and secure method to share information and keep voting registration records up-to-date. Through the organization’s dedicated resources, member states have the tools they need to tackle one of the persistent challenges facing election administration: maintaining an accurate and current voter registration database. Between 2012 and 2021, ERIC has provided member states with reports identifying nearly 25.6 million out-of-date voter records and nearly 56 million likely eligible but unregistered individuals. With this addition to the Election Performance Index, therefore, we hope to capture, celebrate, and even encourage future collaboration to address the challenge of keeping voter roles accurate and up-to-date.

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Joelle Gross is a Senior Research Support Associate at the MIT Election Data + Science Lab. Joelle joined the Lab in July 2021 after graduating with a B.A. from the University of Pennsylvania.

Topics Voter list maintenance