Reviewed and updated October 9, 2026 by the SearchSystems.net editorial team. The arrest counts are the ones each agency reported to the FBI, as the FBI held them on October 8, 2026. The jail figures are from the Vera Institute of Justice's Incarceration Trends data. Every office link was opened and checked against the office's own site between September 23, 2026 and September 25, 2026.
Mount Vernon, New York, in Westchester County, has about 72,000 residents (2024 Census Bureau estimate). A person kept in custody after an arrest in Mount Vernon is held at the county jail, and the jail's record of each person held is a public record. This guide says where to look for someone in custody, what the jail holds and who books people into it.
This guide covers the search, the jail, who books people, state prison and common questions.
Related guides: Mount Vernon public records, Westchester County inmate search, Mount Vernon arrest records, Mount Vernon warrants, Mount Vernon criminal records, Mount Vernon court records, New York arrest records and New York inmate search.
Finding Someone in Custody in Mount Vernon
The county jail holds everyone kept in custody after an arrest in Mount Vernon, from every agency.
SearchSystems opened and checked the custody page of the sheriff's office at correction.westchestercountyny.gov/westchester-inmate-search (page title: Westchester Inmate Lookup), which answered when SearchSystems opened it on September 23, 2026.
Someone booked recently shows on that page; someone cited and released at the scene, or held a few hours at a city station, does not.
The Westchester County Jail by the Numbers
So far in 2026 the jail has held about 550 people on an average day, down from about 1,020 in 2019. Its rated capacity in 2023, the last year with a capacity figure, was 1,808 beds, and it ran at 39 percent of it that year. The figures are from the Vera Institute of Justice's Incarceration Trends data.
Westchester County has about 1.0 million residents (2024 Census Bureau estimate), so the jail holds about 5 people for every 10,000 residents.
Who Books People Into the Westchester County Jail
The agency that reports for Mount Vernon (filed by the FBI as Mount Vernon Police Department) makes the arrests that end in a booking in and around Mount Vernon.
The FBI's agency list also places these agencies in Westchester County: the Westchester County, Hillview New York City Department of Environmental Protection Police and the Westchester County, Croton-Kensico New York City Department of Environmental Police (other agency); the Purchase State University of New York Police (campus police).
The largest arrest counts reported to the FBI were White Plains's 1,566 for 2025, Yonkers's 1,412 for 2025 and Peekskill's 980 for 2025.
Together, the 31 agencies in Westchester County with all twelve months of 2025 on file reported 8,190 arrests to the FBI that year. Those kept in custody were booked into the county jail; a person cited and released at the scene was not.
The counts, agency by agency and year by year, are in Mount Vernon arrest records.
From the Jail to State Prison
A sentence of more than a year is served in state prison, not the jail; the New York State Department of Corrections and Community Supervision lists its inmates at nysdoccslookup.doccs.ny.gov.
Frequently Asked Questions
How do I find an inmate in Mount Vernon?
Look on the custody page of the sheriff's office at correction.westchestercountyny.gov. It covers people booked into the county jail.
How many people are in the Westchester County jail?
About 550 on an average day so far in 2026, against a rated capacity of 1,808 beds.
Where do people sentenced to prison in Westchester County go?
To a facility of the New York State Department of Corrections and Community Supervision; its inmate locator is at nysdoccslookup.doccs.ny.gov.
Is this the official Mount Vernon website?
No. SearchSystems.net is an independent public records guide, online since 1997. It links to the official city, county, court and state offices described above and does not hold records, charge for them or take requests.