Prop 18
Primary Voting for 17-Year-Olds
Constitutional Amendment
Expand Voting to 17-Year-Olds

Allows 17-year-olds who will be 18 at the time of the next general election and are United States citizens and residents of California to vote in any primary or special elections.

Vote YES

Jump to SPUR’s Recommendation

What the Measure Would Do

The California Constitution authorizes any person who is a United States citizen, a resident of California and at least 18 years of age to vote. This measure would permit 17-year-olds who are United States citizens and residents of California to vote in any primary or special election if they will be 18 years old at the time of the next general election.

If California voters approve this measure, the state expects to incur one-time costs associated with updating voter registration systems and estimates that counties will pay between several hundreds of thousands of dollars and $1 million dollars every two years as a result of sending voting materials to eligible registered 17-year-olds.1

The Backstory

Voting in local, state and federal elections in most of the United States is restricted to those 18 years or older; however, 18 states and the District of Columbia allow 17-year-olds to vote in primary elections if they will be 18 by the day of the general election.2 If Prop 18 passes in November, California will be added to this list.

Voter engagement has remained chronically low in the United States, particularly among young voters. Since the U.S. Census Bureau began tracking voter-age data in 1964, young adults have had the lowest voter turnout of any age group.3 This can be partially attributed to barriers to participation that impact young voters, including the many transitions they face, such as moving out of their families’ homes, starting a career or going to college.

Research shows that lowering the voting age spurs short-term and long-term gains in civic engagement. When young voters enter the electorate, they impact the voter turnout of older family and community members.4 Additionally, studies illustrate that the earlier people start voting, the more likely it is that voting will become a long-term habit.5

In addition to spurring gains in voter turnout, this measure will make the general election ballot more representative of the electorate by allowing the full electorate to participate in the preceding primary election.

This measure was approved by two-thirds of the membership of each house of the California State Legislature and must be placed on the ballot because it amends the state constitution. It requires a simple majority (50% plus one vote) to pass.

Equity Impacts

This measure would impact a narrow subset of 17-year-old Californians. Prop 18 could inspire a habit of voting among young people of color, but the impacts of this are unknown.


  • Legalizing voting at a younger age could improve turnout for younger voters and their families.
  • Voting earlier in life has been shown to lead to stronger voting engagement throughout a person’s lifetime.
  • Research has shown that 17-year-olds are sufficiently developed in their analytical, independent, and empathetic cognitive abilities to make thoughtful voting decisions.6
  • Young people are experiencing significant negative impacts of the COVID-19 pandemic and the government’s response. Including 17-year-olds in the democratic process will provide them with greater agency over the systems and institutions that directly impact their lives.
  • By allowing this subset of the population to vote in California’s primary elections, the general election ballots will be more representative of the full electorate.


  • SPUR could not identify any downsides to this measure.
SPUR's Recommendation

SPUR has advocated for decades to increase participation in the civic decision-making process. We believe responsive, effective government requires a high level of involvement by a state’s residents. This measure would open participation in public decisions to more citizens who we believe could make conscientious voting decisions. Additionally, engaging youth in the democratic process could improve the health of our democracy overall by heightening interest in local civic issues and contributing to better youth turnout and lifetime voter engagement.

Vote YES on Prop 18 - Primary Voting for 17-Year-Olds



3. Young-Adult Voting: An Analysis of Presidential Elections, 1964–2012. April, 2014.

4.Michael McDevitt and Spiro Kiousis, “Experiments in Political Socialization: Kids Voting USA as a Model for Civic Education Reform,” August 2006.

5. Eric Plutzer, “Becoming a Habitual Voter: Inertia, Resources, and Growth,” American Political Science Review 96/1 (March 2002): 41–56.

6.  Laurence Steinberg, Elizabeth Cauffman, Jennifer Woolard, Sandra Graham, Marie Banich, “Are Adolescents Less Mature Than Adults?: Minors’ Access to Abortion, the Juvenile Death Penalty, and the Alleged APA “flip-flop,” American Psychologist Journal, 64(7), October 2009, pages 583-594,