About 11 million Californians are on the state-authorized donor registry, Donate Life California, which manages the list, and the California Department of Motor Vehicles announced Tuesday.
"Your registration gives hope to the 21,000 people who wait for the gift of life in California. Some will die waiting for an organ transplant that doesn't come in time due to the lack of available organs," said Cindy Siljestrom, Donate Life California Board President.
One in three adults in the state is a registered donor, Siljestrom said.
About 95 percent of those on the list registered while applying for or renewing their California driver license at the DMV.
California Assembly Speaker John Pérez said the registry makes a "profound difference" for people waiting for a transplant. His father became an organ donor after passing away a few years ago.
More than 21,000 people, or about 20 percent of the national list, who wait for an organ transplant live in California.