Mercer County Tax Records

Mercer County property tax records are held by the Board of Taxation and by local tax assessors in each of the county's 12 municipalities. The county seat is Trenton, which also serves as the state capital of New Jersey. Property owners, title companies, and prospective buyers use these records to check assessed values, confirm tax payments, and review ownership details. The Board of Taxation office is in the Mercer County Administration Building and handles assessment appeals, equalization, and annual certification of tax rolls across the county.

Mercer County Board of Taxation

The Mercer County Board of Taxation oversees property tax administration for all 12 municipalities. This board certifies local tax lists each year, hears assessment appeals, and sets equalization ratios that apply across the county. Under N.J.S.A. 54:4-1, all real property in New Jersey must be assessed at 100% of true market value. The board works to make sure that local assessments stay in line with this standard throughout Mercer County.

Each of the 12 municipalities in Mercer County has its own tax assessor who sets the assessed value of each parcel. The municipal assessor creates and updates tax maps, processes exemptions and deductions, and maintains records on property sales and transfers. When a town conducts a revaluation, the county board reviews the results and certifies the new values. The board also calculates the general tax rate for each town, which is the rate applied to every taxable parcel in that district. Mercer County towns include Trenton, Hamilton Township, Princeton, Lawrence Township, Ewing Township, West Windsor Township, East Windsor Township, Hopewell Borough, Hopewell Township, Pennington Borough, Hightstown Borough, and Robbinsville Township.

You can reach the Board of Taxation at the Mercer County Administration Building in Trenton. Staff can answer questions about the appeal process, equalization tables, and tax rate calculations. Visit the Mercer County Board of Taxation website for forms and current schedules.

Mercer County Property Assessment Search

The Property Information Portal lets you search Mercer County property tax records by owner name, street address, or block and lot number. Search results show the current assessed value, the tax rate for that municipality, property characteristics such as lot size and building type, and sales history for the parcel. This tool is free to use and does not require an account. It covers all 12 municipalities in Mercer County.

You can also search Mercer County assessment records through taxrecords-nj.com. Select Mercer County and then choose the municipality you need. The site provides current assessment data for each property, along with the owner's name and mailing address as listed on the tax rolls. This is a useful way to compare assessed values across different towns in Mercer County or to look up a specific block and lot.

The State of New Jersey also offers a Property Explorer tool at nj.gov/transparency/property. This interactive map displays assessed values and tax data for parcels statewide, including all of Mercer County. You can zoom into a specific area, click on a parcel, and see the assessment, lot dimensions, and owner information. The data comes from the annual tax lists that each municipality files with the state.

Note: Online assessment records may lag behind recent changes. If a property was recently sold or improved, check with the local tax assessor for the most up-to-date figures.

Property Tax Appeals in Mercer County

Property owners in Mercer County who believe their assessment is too high can file an appeal with the County Board of Taxation. The filing deadline is April 1 of each year. In years when a municipality undergoes a revaluation, the deadline extends to May 1. You must file a petition on the official form, which is available at the Board of Taxation office or on the county website. There is no fee to file a standard appeal with the county board.

The board schedules hearings for each appeal, usually within a few months of the filing deadline. Property owners present evidence showing why the assessed value does not match the true market value of the property. Common forms of evidence include recent comparable sales in the same town, an independent appraisal, or photos showing the condition of the property. The board issues a written judgment after each hearing.

Under P.L. 2017, c. 128, properties assessed above $750,000 may be appealed directly to the Tax Court of New Jersey instead of the county board. This route is more formal and typically involves legal representation. Most residential appeals in Mercer County go through the county board first. If either side disagrees with the board's decision, they can appeal to the Tax Court within 45 days.

Mercer County Municipal Tax Assessors

Each municipality in Mercer County employs a tax assessor who values every property within that town. The assessor inspects properties, reviews building permits, and updates records when ownership changes. They also process applications for veterans' deductions, senior citizen and disabled person deductions, and homestead exemptions. Under New Jersey law, qualifying veterans receive a $250 annual deduction from their property tax bill. Senior citizens and disabled persons who meet income limits receive a $250 deduction as well.

The Ewing Township Tax Assessor website is a good example of the resources available at the local level in Mercer County. The page links to the NJ Division of Taxation, the Mercer County Board of Taxation, the Taxpayer Bill of Rights, and general property tax information. It also lists current relief programs for property owners. New in 2025, New Jersey introduced a Single Combined Application for the Property Tax Reimbursement program (Senior Freeze), the ANCHOR benefit, and the Stay NJ program. This combined form is for residents age 65 and older or those receiving Social Security Disability benefits. The filing deadline for the combined application was October 31, 2025.

The Trenton Tax Assessor handles property assessments for the city of Trenton, which is the largest municipality in Mercer County. This office maintains tax maps, processes deduction applications, and provides information about assessment appeals. As the state capital, Trenton has a large number of government-owned properties that are exempt from taxation, which affects the overall tax base and rate for the city.

Note: Contact your local municipal tax assessor for the most current assessment on a specific property. Assessment records are public under the New Jersey Open Public Records Act (OPRA), N.J.S.A. 47:1A-5.

Mercer County Land Records

The Mercer County Clerk records and stores all land transaction documents for the county. This includes deeds, mortgages, liens, and easements. The office has records dating back to 1838, when Mercer County was established from portions of Burlington, Hunterdon, and Middlesex counties. Documents recorded from 1990 forward are searchable online through the clerk's website.

When a property is sold in Mercer County, the deed is recorded with the County Clerk to create an official public record of the transfer. The recording process establishes the legal chain of title for each parcel. Title companies, attorneys, and property buyers rely on these records to verify ownership before any transaction closes. The clerk also handles trade name registrations and notary commissions for Mercer County.

For records before 1990, you need to visit the clerk's office in Trenton. Staff can help you search the grantor and grantee indexes that cover earlier periods. Older records are stored in bound volumes and on microfilm. The clerk charges standard fees for copies and certifications per the state fee schedule.

New Jersey Tax Resources for Mercer County

The New Jersey Division of Taxation publishes property tax data, guidance documents, and forms that apply to every county in the state, including Mercer. The division's general property tax information page explains how assessments work, what exemptions and deductions are available, and how tax rates are calculated. This is a good starting point for property owners who want to understand the system before contacting their local assessor.

Public records requests in New Jersey are governed by the Open Public Records Act. If you need specific tax documents from a Mercer County municipality or from the county itself, you can file an OPRA request. The state operates an online portal at njopraportal.com where you can submit requests to participating agencies. Government agencies must respond within seven business days. There is no charge for inspection of records, but agencies may charge for copies.

The Division of Taxation also maintains the SR-1A system, which collects data on every real estate sale in the state. This data feeds into the equalization process and helps the Mercer County Board of Taxation set accurate ratios. The annual Equalization Table shows the ratio of assessed value to true value for each municipality in the county. A ratio significantly above or below 100% may trigger a revaluation order for that town.

Mercer County Tax Rates

Property tax rates in Mercer County vary by municipality. Each town has its own general tax rate, which is set each year based on the total amount of the municipal budget, the school district budget, and the county tax levy divided by the total assessed value of all taxable property in that town. A property's annual tax bill equals its assessed value multiplied by the general tax rate.

Mercer County is home to Princeton University, one of the largest landowners in Princeton. Much of the university's property is tax-exempt as an educational institution. This reduces the taxable base in Princeton and affects the rate paid by other property owners in that municipality. Similar dynamics exist in Trenton, where a large share of property is owned by state and county government and is therefore exempt from local property taxation.

Tax bills in Mercer County are mailed by each municipality's tax collector. Payments are due in four quarterly installments: February 1, May 1, August 1, and November 1. Interest accrues on late payments at rates set by state law. If a property owner falls behind, the municipality may place a tax lien on the property and sell that lien at an annual tax sale. Mercer County municipalities conduct tax sales as required under N.J.S.A. 54:5-19.

Cities in Mercer County

Mercer County has 12 municipalities. Each one has its own tax assessor and tax collector who manage property records at the local level. The county Board of Taxation coordinates assessment standards across all towns.

Other municipalities in Mercer County include Princeton, Lawrence Township, Ewing Township, West Windsor Township, East Windsor Township, Hopewell Borough, Hopewell Township, Pennington Borough, Hightstown Borough, and Robbinsville Township.

Nearby Counties

These counties border Mercer County. Property owners near county lines should confirm which jurisdiction holds their tax records. Each county maintains its own Board of Taxation and assessment system.