Massachusetts has 40 prisons and jails: 0.8% of the US total of 4,960. That ranks #38 by count and #48 per person (0.56 per 100,000 residents) of 51.
Source: HIFLD Prison Boundaries (U.S. Department of Homeland Security), final release, 2025. Each facility at the centre of its boundary. The Prison Policy Initiative counts 5,077 facilities (2026); counts differ by which kinds of facility are included.
Licence: U.S. government data: no copyright, free to reuse
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<iframe src="https://get-instamaps.com/embed/rankings/prisons-jails/massachusetts" width="100%" height="440" style="border:2px solid #111" loading="lazy" title="Massachusetts prisons and jails map — InstaMaps"></iframe>Dukes County House of Correction and Jail · Bristol County Ash Street Jail and Regional Lock-Up · Bristol County House of Correction and Jail · Bristol County Sheriff's Office Women's Center · C. Carlos Carreiro Immigration Detention Center · Barnstable County Correctional Facility · Massachusetts Alcohol and Substance Abuse Center - Plymouth · Plymouth County Correctional Facility · Bridgewater State Hospital · Massachusetts Treatment Center · Old Colony Correctional Center · Western Massachusetts Recovery and Wellness Center
"Massachusetts has 40 prisons and jails, #38 in the US by count and #48 per person (HIFLD Prison Boundaries, 2025, mapped by InstaMaps)." Free to quote with a link to this page. Population: US Census 2024 estimates.