California runs one of the largest correctional systems in the world. With tens of thousands of people behind bars at any given moment, the state spends more per inmate than nearly any other jurisdiction on Earth and yet the majority of people sitting in its county jails have not been convicted of a crime. Understanding California’s incarceration system means grappling with two distinct institutions: state-run prisons and county-run jails, each serving a different population, funded differently, and governed by different rules.
California’s incarceration system is split into two tiers. State prisons, operated by the California Department of Corrections and Rehabilitation (CDCR), house people convicted of felonies serving longer sentences. County jails, operated by local sheriffs, hold people awaiting arraignment, trial, or sentencing, as well as those serving shorter sentences for lesser offences. In total, roughly 382,700 adults were under some form of correctional supervision in California in 2024, including those in prisons, jails, on parole, or on probation.
California’s state prison population has declined significantly over the past decade — from over 120,000 in 2018 to 91,556 by May 2024, a reduction of roughly 25%. Yet even as the population has shrunk, the cost per inmate has skyrocketed. In the 2025–26 fiscal year, California is projected to spend approximately $127,800 per incarcerated person annually. At its recent peak, that figure hit a record-breaking $132,860 per person per year, nearly twice the annual tuition at a major private university. Since 2010–11, the per-inmate cost has risen by roughly $78,900, or 161%, driven primarily by soaring health care and security expenses.
More than half of the California Department of Corrections and Rehabilitation(CDCR’s) budget, about 54%, is consumed by prison operations. Prisoner health care accounts for another 28%. Only about 4% goes toward rehabilitative programs such as education, job training, and substance abuse treatment. Governor Newsom’s most recent budget proposed $18.1 billion for the CDCR, up from $15.7 billion when he first took office in 2019.
Perhaps the most striking fact about California’s county jails is this: approximately 79% of the people inside them are non-sentenced. They are awaiting arraignment, bail hearings, trial, or sentencing. They have not been found guilty. They remain incarcerated because they cannot afford bail, or because their case has not yet been resolved. As of mid-2025, about 60,300 people were held in California’s county jails. Men make up 88% of that population, and people charged with felonies account for 88% of the jail headcount.
Each year, at least 368,000 different individuals are booked into California’s local jails. People cycle through quickly, some held for hours, some for months or even years. The snapshot population of around 60,000 vastly understates the actual scale of jail involvement across the state. No discussion of California jails is complete without addressing Los Angeles County, which operates what is widely considered the largest jail system in the world. During the third quarter of 2024, the average daily inmate population in LA County’s jail network was 12,756 people. The system has been the subject of decades of federal oversight, civil rights litigation, and reform efforts. LA’s jail population is disproportionately composed of people with serious mental illness, substance use disorders, and housing instability, challenges the jail system is ill-equipped to address.
California’s incarceration rate stands at approximately 494 people per 100,000 residents higher than virtually all democratic countries. Germany’s rate is around 70 per 100,000; France’s is about 95. Even within the United States, California’s rate reflects a system that, despite years of reforms, still relies heavily on incarceration as the primary response to crime and social disorder. For every 100,000 Californians, nearly 500 are behind bars with consequences that ripple outward for generations.
California’s correctional system presents a troubling paradox. The state spends close to $130,000 per inmate per year in state prisons and yet most of the people in its county jails have not been convicted of any crime. Reformers argue that the path forward requires investing earlier and further upstream in mental health services, housing, drug treatment, and alternatives to incarceration rather than continuing to funnel billions into a system that has failed to significantly reduce crime or recidivism. The debate is unlikely to be resolved soon, but the numbers demand serious engagement.
Key Statistics at a Glance
State prison inmates (May 2024): 91,556
County jail inmates (mid-2025): ~60,300
Total adults under correctional supervision: ~382,700
Annual bookings into county jails: 368,000+
Cost per state inmate per year: $127,800 – $132,860
Total CDCR budget: $18.1 billion
Incarceration rate (per 100,000): 494
Percent of jail inmates not yet convicted: ~79%