The Department of Assessment is responsible for developing fair and equitable assessments for all residential and commercial properties in Nassau County on an annual basis. Nassau County’s assessment roll includes over 423,000 properties with a value of $264 billion. It is the second largest assessing entity in the State of New York after New York City.

The Department of Assessment collects and records relevant residential, commercial and industrial property information. We validate over 20,000 building permits each year by confirming all new construction and including the new value on the next assessment roll. The department maintains property records, tax maps, answers public inquiries, assists the public through its outreach program, and processes applications for property tax exemptions and the Basic and Enhanced STAR programs for qualifying Nassau County homeowners.