How Provisional Ballots Can Strengthen Same-Day Registration

The American election system is highly decentralized, resulting in substantial differences between states on a wide range of election policies. Voter registration deadlines are one such example, with some states setting the deadline up to 30 days before Election Day and others allowing voters to register at the polls immediately before casting a ballot. Policy discussions around this topic often focus on whether or not to permit same-day registration and how that choice impacts voter convenience and turnout, administrative complexity, and election security. However, states that opt for same-day registration must also consider how to implement the policy in a way that bolsters public confidence in its security.

Same-day registration refers to the process by which voters register to vote and receive a ballot during a single visit to a polling location. Nationwide, approximately half of states permit same-day registration in at least some circumstances. The most common approach is to allow it for all general elections, both on Election Day and during the early voting period. Other states specify more limited circumstances for same-day registration, including New Hampshire (Election Day only), North Carolina (early voting only) and Alaska and Rhode Island (presidential elections only). Overall, the Election Assistance Commission reported 2.2 million registration transactions at polling locations in 2024—most of them updates rather than new registrations. This means same-day registrants accounted for less than 1 percent of the 158 million ballots cast in the 2024 general election.

From an administrative perspective, same-day registration merges two core functions into a single interaction between voter and election worker: registering to vote and checking in at a polling location. The first part of the process establishes the individual’s general eligibility to vote by collecting proof of identity and residency, while the second verifies the voter’s eligibility to vote in the current election by determining whether they have already registered and voted at another location.

States with same-day registration follow three main approaches to confirm an individual’s eligibility to receive a ballot. The first is using technology, such as e-pollbooks, to provide real-time voter registration information across polling locations that indicates whether a person has already voted at another location. The second is conducting post-election checks to identify any voters who cast multiple ballots and prosecute those who violate prohibitions on double voting. The third is using provisional ballots for all Election Day registrants and completing verification at some point after polls close.

Under either of the first two approaches, the final determination for issuing and counting a ballot cast by a same-day registrant is made at the point of the registration transaction. States utilizing electronic poll books that can access the statewide voter registration database or otherwise share information between polling locations in real time can determine with high certainty whether a voter already registered or voted at another polling location before issuing a ballot. On the other hand, jurisdictions without the capability to share information on Election Day must rely on post-election procedures and audits to identify any voters who cast multiple ballots.

Procedures in place to prevent double voting through the same-day registration process are largely effective but add another layer of complexity to the Election Day process for workers. Provisional ballots can help alleviate that additional complexity at the polling location by shifting the final determination of eligibility to the post-election period while maintaining the same level of convenience for voters who are still able to register and vote in a single visit to the polls.

Utah and Virginia rely exclusively on provisional ballots for anyone who registers at a polling location on Election Day or during the early voting period. Meanwhile, Nevada allows same-day registrants to vote a regular ballot during the early voting period (in some instances) but requires a provisional ballot on Election Day. New Mexico requires voting locations without real-time access to the state voter- registration database to issue provisional ballots to anyone utilizing same-day registration.

Using provisional ballots or confirming eligibility through real-time access to the voter registration database provides election workers with the same level of confidence in the voter’s eligibility; however, the provisional approach is preferable overall as it helps distribute the workload to the post-election period. Both approaches are better than catching an individual who voted twice and whose ballots have already been processed, though such instances are exceedingly rare in practice.

Overall, strong arguments remain for simply requiring voters to register before Election Day. But by using provisional ballots, states that permit same-day registration can do so in a manner that minimizes the administrative burdens on election workers while protecting the security of the election process.