Is voter fraud a problem in the US?

Short answer: Actual voter fraud is extremely rare, but perceptions of it as a "problem" remain widespread and politically divided.

What the empirical evidence shows:

Decades of academic and nonpartisan research have consistently found that voter fraud occurs, but at vanishingly small rates. One landmark Brennan Center report reviewed elections that had been meticulously studied for voter fraud and found incident rates between 0.0003 percent and 0.0025 percent, concluding an American is more likely to be struck by lightning than to impersonate another voter at the polls.

Multiple independent studies back this up:

Experts summarize it bluntly: "There are a few cases of election fraud in every campaign... But it's not systemic. It's not widespread. It's generally not organized, and I don't think it's ever affected the actual outcome, but people often pick on isolated cases and turn it into a systemic and widespread pattern."

Even after the highly scrutinized 2020 election, an AP count of disputed fraud cases in six battleground states found fewer than 475 votes combined — less than two-tenths of one percent of Biden's margin — and no systematic collusion or "rigging."

But public perception tells a different story:

There's a stark gap between the evidence and what Americans believe. A Pew Research Center survey found that 54% of Republicans believe voter fraud is a major problem in U.S. elections, compared to 6% of Democrats. Similarly, a Fox News poll found that 61% of Americans believe "there is a lot of voter fraud in elections."

Researchers note this perception gap has real consequences: large shares of registered voters consider various types of election fraud to be common or occasional, which is itself concerning since people who believe fraud is common are less likely to participate in elections or trust the electoral process.

Bottom line: By virtually every rigorous empirical measure, voter fraud in the U.S. is real but exceptionally rare and has not been shown to affect election outcomes — including in the presidential level. It is not a "problem" in the sense of being widespread or systemic. However, it remains a significant political issue because a large share of the public (especially along partisan lines) perceives it as a major threat, regardless of what the data shows.