The SF Bay Area just gained over a quarter million people in an error correction issued by the U.S. Census Bureau — but the error had to do with the North Bay.

The December update from the U.S. Census Bureau, which reflected estimated population changes between July 2021 and July 2022, showed a slight decline in the Bay Area's population in the second year of the pandemic — though far less sharp a decline as happened in the previous 12 months of widespread relocations and remote work.

But the Census Bureau made a few oopsies in that count, as well as the counts of a few other metro areas, according to a notice posted Tuesday by the Federal Register. As the Associated Press reports, the Bay Area error means that the 2022 population of the region goes from 3.2 million residents to 3.5 million residents. Those missing 300,000ish residents came from the San Rafael-Novato area, which the bureau now says was mistakenly left out of the SF metro area count.

To be clear, this is just the bureau's estimate for what it calls the "San Francisco-Oakland urban area," and other counts of the metro area sometimes include Berkeley and a big swath of the East Bay, totaling 4.6 million. The entire nine-county region had an estimated population of 7.56 million as of last July — and per Socketsite, that was still down overall from 2021 by 177,000 people, unless this Census snafu impacts the overall Marin County count as well.

Along with the Bay Area adjustment, the Census Bureau adjusted the Atlanta urban area up from 4.9 million to 5.1 million due to a similar omission. And the population of the New Orleans urban area grew to 963,212 residents from 914,531.

It will be interesting to see how much the Bay Area population either leveled off or grew between July 2022 and July 2023, numbers which we should see in December.

San Francisco proper saw a net drop in population of 36,084 between 2020 and 2022, which included a fair amount of return migration in the second year of the pandemic, following the larger one-year decrease (54,800) in 2020-2021.

These one-year updates that occur between decennial censuses are not based on the same house-by-house counting methodology of the census, but are educated estimates based on a number of factors and data points tracked by the bureau.

Analysis by the Census Bureau in May found that coastal cities largely lost population during the pandemic, while Sun Belt cities like Austin, Phoenix, Dallas, Atlanta, and Jacksonville all saw growth.

Related: Census: Santa Cruz Grew Quickly, SF Shrank Less Quickly In Second Year of Pandemic; Sun Belt Cities Saw Most Growth

Photo: Chris Leipelt