Guides
California Proposition 103 explained
What California's 1988 Prop 103 did: the 20% rollback, prior approval of rates, the Good Driver Discount, ranked rating factors and paid consumer intervenors.
proposition 103 is the voter initiative, approved on November 8, 1988, that still governs how car insurance is priced in California. It ordered insurers to cut rates at least 20%, and it requires the Insurance Commissioner to approve rates before insurers use them. It also ranks driving record, annual mileage and years of driving experience as the main pricing factors and created a Good Driver Discount of at least 20%. Anyone can challenge a rate request and be paid for helping, and the commissioner became an elected office. The rules cover auto, home and most other property and casualty insurance.
What the initiative did
Prop 103 added Article 10 to chapter 9 of the California Insurance Code (sections 1861.01 to 1861.16), plus a few other sections. The main pieces:
| Provision | What it says | Code section |
|---|---|---|
| Rate rollback | Policies issued or renewed from November 8, 1988 had to cost at least 20% less than on November 8, 1987. Rates were frozen for a year unless an insurer faced insolvency | 1861.01 |
| Prior approval | From November 8, 1989, rates must be approved by the commissioner before use | 1861.01(c), 1861.05 |
| Rating factors | Auto rates are based, in decreasing order of importance, on driving safety record, annual miles driven, and years of driving experience, then other approved factors | 1861.02 |
| Good Driver Discount | Qualifying drivers pay at least 20% less than they otherwise would for the same coverage | 1861.02, 1861.025 |
| No penalty for being new | The absence of prior insurance cannot by itself be used to set auto rates or eligibility | 1861.02 |
| Consumer participation | Anyone may intervene in rate proceedings and be paid for a substantial contribution | 1861.10 |
| Elected commissioner | The Insurance Commissioner is elected, like the governor, for up to two four-year terms | 12900 |
Prior approval: how a rate change gets approved
Most states let insurers start using new rates and review them afterward, or simply file them; see how car insurance rate approval works. California is a strict prior approval state. Under section 1861.05:
- The insurer files a rate filing with supporting data. It carries the burden of proving the rate is justified.
- The commissioner may not approve a rate that is "excessive, inadequate, unfairly discriminatory" or otherwise illegal. The review must account for the insurer's investment income.
- The Department of Insurance gives public notice of the application.
- A consumer can request a hearing within 45 days of the notice. If a personal-lines increase exceeds 7% (15% for commercial lines), a timely request means a hearing must be held. The commissioner can also call a hearing on their own.
- Without a hearing, the application is deemed approved 60 days after notice. Decisions are generally due within 180 days.
Insurers argue that this process is slow and keeps rates below cost after claim costs jump. The argument sharpened when claim costs spiked: California's auto liability loss ratio rose from 51.9% in 2020 to 80.6% in 2022, according to NAIC data. Nationally, the Insurance Research Council found that average rate approval times grew about 40% from 2010 to 2023. See California car insurance: costs, Prop 103 and the 2025 minimums for how this has played out on prices.
The Good Driver Discount
Under section 1861.025, you qualify if you have been licensed for the past three years. In that time you must not have had more than one violation point. An at-fault crash that caused only property damage counts as a point. You also must not have been the at-fault driver in a crash that caused injury or death, among other conditions. A qualifying driver must be charged at least 20% less than the same driver would pay without the discount at that insurer.
A worked example
Say an insurer's rate for a given car, coverage and territory is $2,000 a year for a driver without the Good Driver Discount. A driver who qualifies must pay no more than $1,600 for the same coverage. A single speeding ticket is one point and usually still qualifies. Add an at-fault fender-bender in the same three years and the driver can lose the discount, and the price can jump by a quarter or more at renewal. That is the main reason a California ticket or crash costs what it does.
Rating factors and what is banned
Because the law ranks driving record, mileage and experience first, factors that dominate elsewhere count for less in California. Other approved factors, such as where you live, rank below those three under the law. California does not allow a credit-based insurance score in auto pricing. Gender-based rating was ended by regulation from January 1, 2019. In September 2026, the Department proposed ending the use of marital status; that proposal was not final when this guide was written. See credit-based insurance scores and car insurance and how age, gender and marital status affect car insurance.
Intervenors: consumers in the rate room
Section 1861.10 lets "any person" intervene in a rate proceeding, challenge the commissioner's actions, or enforce the article in court. Consumer representatives who make a "substantial contribution" to a decision are awarded reasonable advocacy and witness fees. When the proceeding concerns a rate application, the insurer that filed pays the fees. Industry representatives do not receive compensation, according to the Department of Insurance.
In 2026 the Department adopted what it called the first overhaul of the intervenor process in 35 years. The new rules clarify what counts as a substantial contribution, require compensation to be documented and tied to the issues in a proceeding, and expand public reporting (CDI, April 2026). The rules took effect in August 2026.
What it has meant for drivers
The Department says its rate review saved Californians $6.6 billion in premiums from 2019 to 2025. It also says it secured $3.3 billion in refunds for drivers during the COVID-19 pandemic. Insurers counter that slow approvals make it harder to keep writing new business when costs rise quickly. Both effects follow from the same design. Rates cannot rise until the state agrees they must.
For drivers, the practical points are:
- Your record matters most. Protecting the Good Driver Discount is worth more than almost any other saving.
- Mileage counts. Report your annual miles accurately; overstating them costs you.
- Rate requests are public. You can see pending filings and comment or intervene.
- Complaints go to the Department of Insurance, which also licenses and disciplines insurers; see what your state insurance department does.
Key takeaways
- Proposition 103, approved November 8, 1988, ordered a 20% rollback and requires prior approval of most property and casualty rates in California.
- Auto rates must be driven mainly by driving record, annual mileage and years of experience, in that order.
- Qualifying good drivers must pay at least 20% less than they otherwise would.
- Any person can intervene in rate cases, and consumer intervenors who contribute substantially are paid by the insurer that filed. New intervenor rules took effect in August 2026.
- The law also made California's Insurance Commissioner an elected office.