The Office of Tax Assessor provides assistance to residents and non-residents on matters related to assessing property, the assessment placed on a property, tax deductions, added assessments, and other questions related to establishing the value of property for taxation purposes. The actual billing and collection of taxes is a function of the Tax Collector’s Office, not the Assessor. The Assessor’s Office cannot collect taxes.

The Tax Assessor is a quasi-judicial position, a creature of the Legislature, whose authority is statutory and based in the New Jersey constitution. The function of the Assessor’s Office is to be fair and equitable while maintaining uniformity. Assessments in New Jersey are "ad valorem" which means according to value.

One of the major functions of the Assessor’s Office is establishing the value of all new and improved property that will be used in determining the share of taxes to be levied for the property. The Tax Assessor’s Office is required annually to assess real property at full value as of October 1st of the pretax year. The Assessor does a field inspection, considers sales analysis and market trend studies, and income and expense analysis as part of establishing the assessed value. The assessment is performed in conformance with State statutes and regulations.

The Office of the Assessor Processes Applications For Exemptions and Deductions. The Assessor determines whether the property is taxable. There are several tax exemption and tax deduction provisions in the law such as disabled veterans and senior citizen deductions. (See the Deductions listed below)

The Office of the Assessor maintains the assessment records and is responsible for the maintenance of the Borough tax map. records of property transfers and ownership are kept current. The Office Monitors Building Permits as part of establishing added assessments.

The Assessor represents the Borough in Tax Appeals before the Sussex County Board of Taxation and in State appeals before the Tax Court of New Jersey. A Hopatcong property owner who believes that the assessed value exceeds market value may appeal the assessment to the Sussex County Board of Taxation. The assessed value is being appealed, not the amount of taxes. Appeals must be filed by April 1st, where a municipal revaluation or reassessment has been undertaken a petition must be filed and received by May 1st (or Dec. 1st for Added Appeals) except that properties with an assessed value exceeding $1,000,000 may file directly with the Tax Court in Trenton. Applications for appeal may be obtained from the Sussex County Board of Taxation after February 1st (973-579-0970)