Mercer County, New Jersey
Mercer County · Trenton · the capital still hires a county
Trenton is the seat and the capital. Newark is Essex.
Mercer is the capital county of New Jersey, created 1838, on the Delaware River. Trenton is the seat. Trenton is the capital of New Jersey. That is the sentence this page exists to teach. Newark is the largest city in the state. Newark sits in Essex — already live — and is not the capital. Jersey City is Hudson. Flemington is Hunterdon. New Brunswick is Middlesex. Mercer County, Pennsylvania, is a different state.
Twelve municipalities: East Windsor, Ewing, Hamilton, Hightstown, Hopewell Borough, Hopewell Township, Lawrence, Pennington, Princeton, Robbinsville, Trenton, and West Windsor. Princeton is this county. Hamilton is this county. Trenton is this county and the capital.
This page is Side One for the place. The Sheriff’s job — South Broad Street court security, process, airport, not the Route 29 jail — is taught at Office of the Sheriff — Mercer County.
County Executive plus seven Commissioners
Mercer adopted the Optional County Charter — County Executive form. The County Executive is a four-year elected desk. Seven County Commissioners sit at-large on a stagger. That is not Hunterdon’s five with no Executive. That is not Middlesex’s seven with no Executive.
The Sheriff is a constitutional officer, three years, Article VII, Section II, paragraph 2. The County Executive does not hire this badge. Last regular sheriff general was 2023. Next regular is Tuesday, 3 November 2026. Primary 2 June 2026 already sat. This county is on the 2026 sheriff card. Hudson, Hunterdon, and Middlesex wait until 2028. The Governor is 2029.
Delaware Falls and Assunpink, not the Hudson tubes
The Delaware River, the Falls, and Assunpink Creek are this land. I-95 / I-295, Route 1, and Route 29 are this pavement. The gold dome is the State House — the state, not the county hall. No PATH as the county story. No Newark skyline as this seat. Staff who paste Essex onto South Broad Street are on the wrong county.
How a capital-county public actually files a paper
Each municipality has a site. Princeton’s site does not speak for Hamilton. The Sheriff’s listing speaks for court, process, warrants, transport, and airport security. The Mercer County Correction Center at 1750 Route 29, Hopewell Township is Department of Corrections — a Warden, not this Sheriff. New Jersey State Prison is the state. The County Clerk lists with Mercer County government in Trenton. Do not send an Ewing family to Newark for a county paper. Do not send them to Philadelphia for a New Jersey writ.
Civil Court House, a jail on Route 29 that is Corrections
Crime in Trenton is often Trenton Police. Crime in Princeton is often Princeton Police. New Jersey State Police is the state. Civil process, Superior Court security at 175 South Broad Street, sheriff sales, fugitive work, and Trenton-Mercer Airport are this Sheriff. Jail as a local house is Route 29 Corrections. Rights do not change at the Hopewell line. Remedy for city police is the City. Remedy for a Sheriff’s paper is the Sheriff. Relief when the Delaware floods Trenton is this count first.
A student who stays on South Broad
A student uses town pages, the county jobs board, or the Sheriff’s official listing at 175 South Broad Street. The State House is a field trip. It is not the Sheriff. Outreach that only knows one dome is not doing Hightstown or Robbinsville.
Place snapshot (verify official sources)
- Seat: Trenton · Capital of New Jersey: Trenton (this county)
- Government: County Executive + seven Commissioners at-large
- Sheriff: three years · next regular 2026 · not the Route 29 jail
- Not Essex · Not Newark · Not Hudson · Not Mercer County, Pennsylvania
What this is not
- Not Newark. Not Essex. Newark is the largest city. This is the capital.
- Not Hudson. Not Jersey City. Not Hunterdon. Not Flemington.
- Not Trenton Police as this Sheriff. Not Route 29 Corrections. Not State Prison.
- Not Mercer County, Pennsylvania.
- Not a campaign flyer.