Voter fraud does occur in the US, but documented cases are rare relative to the total number of votes cast.
Here is what is known from studies, audits, and prosecutions:
1. How common is it?
Most academic studies and reviews of election data find the rate of voter fraud is very small.
•Analyses by universities and research organizations, including the Brennan Center for Justice and MIT Election Data and Science Lab, have estimated the rate of fraud at between 0.0003% and 0.0025% of votes cast.
•The Heritage Foundation maintains a database of proven cases of voter fraud. As of 2024, it lists about 1,500 proven cases over a period of more than 20 years, during which billions of votes were cast in federal, state and local elections.
•Associated Press, CISA, and state election audits of the 2020 election found no evidence of fraud at a scale that would have changed the outcome of the presidential election. More than 60 court challenges alleging widespread fraud did not succeed in proving systemic fraud.
Other researchers and groups argue these numbers undercount fraud because fraud is difficult to detect, not all cases are prosecuted, and database studies only count convictions.
2. Types of voter fraud that have been documented:
•Impersonation or double voting: One person voting in the name of another or voting in two states.
•Mail ballot fraud: Fraud involving absentee or mail-in ballots, such as ballot harvesting, coercion, or forging signatures. This is the category where most proven cases that have affected an election outcome have occurred.
•False registration / Ineligible voting: Voting by individuals who are not eligible, including non-citizens or felons whose voting rights have not been restored, or registering with false information.
•Vote buying or coercion
•Election official misconduct: Altering vote counts or ballots.
While rare nationally, there have been local cases where fraud affected the result. For example, a 2018 North Carolina congressional race was overturned and a new election ordered due to an absentee ballot fraud operation.
3. Why there is disagreement about whether it is a "problem":
•Those who say it is not a major systemic problem point to the low conviction rate, multiple layers of safeguards such as voter rolls, signature verification, audits, and ID requirements in many states, and the lack of evidence that fraud has changed the outcome of a statewide or national election in recent decades.
•Those who say it is a problem argue that even a small number of fraudulent votes can affect close local races, that vulnerabilities exist particularly with mail-in voting and outdated voter rolls, and that public confidence requires stricter safeguards such as voter ID, proof of citizenship, and tighter absentee ballot rules.
4. Safeguards in place:
States use voter registration databases, signature matching for mail ballots, identification requirements that vary by state, post-election audits, and cross-state database checks to detect double voting. Federal and state officials also audit election equipment and voter lists before and after elections.
In summary, proven cases of voter fraud exist and are prosecuted every election cycle, but the evidence from research, audits, and courts indicates it occurs at a very low rate and has not been shown to occur at a scale that would alter the results of a modern presidential election, though it has occasionally affected small, local contests.