A commonly expressed concern about vote-by-mail in the United States is that mail-in ballots are sent to dead people, stolen by bad actors, and counted as fraudulent votes. To evaluate how often this occurs in practice, we study the state of Washington, which sends every registered voter a mail-in ballot. We link counted ballots and adminis- trative death records to estimate the rate at which dead people’s mail-in ballots are improperly counted as valid votes, using birth dates from online obituaries to address false positives. Among roughly 4.5 million distinct voters in Washington state between 2011 and 2018, we estimate that there are 14 deceased individuals whose ballots might have been cast suspiciously long after their death, representing 0.0003% of voters. Even these few cases may reflect two individuals with the same name and birth date, or clerical errors, rather than fraud. After exploring the robustness of our findings to weaker conditions for matching names, we conclude that it seems extraordinarily rare for dead people’s ballots to be counted as votes in Washington’s universal vote-by-mail system.