With 10 days until the election, officials say the urgency is greater for voters living outside urban centers, where ballot postmarking and delivery may take longer under a consolidation plan affecting regional postal processing.
Announced in 2021 as part of a long-term strategic plan, the changes could lead to delays in delivery of mail or postmarking.
Political data expert Paul Mitchell said this might complicate that timeline for rural voters.
"The state law allows for ballots to be counted as long as they're postmarked by Election Day. But in a lot of rural areas, they're no longer postmarked at the local post office. They're only post marking once it actually gets to the central sorting facility, which is in the urban areas of the state," Mitchell said. "So voters in these areas should know that if it's within a week of the election and they haven't mailed their ballot to take it to a local drop off, take it to a vote center. But beware of mailing your ballot too late."
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In Marin County, officials have added election drop boxes near two affected post offices to help ensure ballots are collected on time.
Registrar of Voters Natalie Adona said delays could catch some voters off guard.
"That becomes an issue for folks who are sort of hanging on to their ballot, because you might, you know, think, oh, I've dropped this off in the mailbox surely, they'll postmark it on the same day," Adona said. "Especially if they're waiting until Election Day to drop off the ballot to go inside and ask for that, that time stamp, it's called a round stamp."
Unlike USPS mailboxes, county-run ballot drop boxes are handled directly by election officials and collected frequently.
Alameda County interim Registrar of Voters Cynthia Cornejo said those drop boxes offer a more reliable alternative as Election Day nears.
"They're picked up every day at times as we get busier, as we get closer to the election, two, three, four times a day, those boxes are picked up and brought back directly to our central location here in Oakland," Cornejo said. "Definitely use drop boxes."
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Still, experts note that many voters wait until late in the process to make decisions, which could increase the risk of delays.
Mitchell advised those voters to act sooner.
"So while some voters are interested in waiting till the very end to determine who to vote for, mail your ballot within a week of the election if you're living somewhere that is not an urban center," he said.
According to the Los Angeles Times, four times more ballots arrived after Election Day during the 2025 special election for Proposition 50 than they did in the 2024 election, underscoring concerns about timing.
Cornejo encouraged voters to plan ahead. "Mail that ballot in early if you're going to do that or drop it off directly to their local elections official," she said.
As of Friday, just under 7% of eligible Californians have returned their ballots, according to the California Secretary of State's office.