Nearly 150,000 mail-in ballots were rejected in California’s June primary election, indicating a significant rise from past elections. Despite efforts to facilitate voting and increase participation, the state’s attempt appears ineffective, evidenced by slow vote counts extending for weeks.

Changes to Voting Process

California implemented changes aimed at voter turnout improvement. Every voter now receives a mail-in ballot that can arrive up to seven days after Election Day and still be counted, provided it is postmarked by Election Day. Despite this leeway, late-arriving ballots remain the primary reason for rejections, as per the data from the state secretary’s office.

Late Postmarks and Rejections

The rise in rejected ballots is likely tied to ballots postmarked after Election Day. This issue may stem from the U.S. Postal Service changes affecting the application timing of postmarks. Data reveals that in June, 148,241 mail ballots were rejected, making up 1.73% of all mail ballots, up from 108,982 rejections in the 2024 primary.

Lateness accounted for 93,479 rejected ballots, with previous counts showing about 70,000 in 2022 and 76,000 in 2024. This increase coincided with a late surge in ballots during a competitive governor’s race in June.

“Ballots rejected due to lateness are caused primarily to being postmarked too late to count, not because they arrived too late to count,” said Kim Alexander, president of the nonpartisan California Voter Foundation.

Concerns Over Postal Service Changes

Lawmakers express concern that U.S. Postal Service policy changes might affect postmark dates. A letter from Democratic senators urged the Postal Service to reconsider mail-processing changes. Updated policies suggest postmarks may reflect the date of processing at a center rather than the initial mail receipt. Consolidations moving centers further from communities could delay postmarks.

Wisconsin Democrats, U.S. Sen. Tammy Baldwin and Gov. Tony Evers, called on the Postal Service to address similar delays in their state. A federal judge recently halted an executive order by President Donald Trump, targeting federal voter lists and mail ballot provisions, amid these issues.

Counties with High Rejection Rates

Tulare County in California’s Central Valley had the highest mail ballot rejection rate in June at 3.52%, followed by Alpine and Merced Counties, both at 3.36%. Other notable reasons for rejections included mismatched signatures or missing signatures (44,000 ballots) and ballots missing from envelopes or multiple ballots in one envelope (over 8,300 ballots).

California’s Slow Vote Count

California remains slow in vote counting compared to other states such as Florida and Texas. President Donald Trump criticized California’s process, and the Republican-led Department of Justice investigated Los Angeles County’s elections following the June primary. Despite delays, mail voting remains popular across party lines, with fraud remaining rare: roughly four cases per 10 million ballots, according to a Brookings Institution report from 2025.