A property tax lien is a lien or claim for money due to a federal, state, or local government for unpaid and delinquent taxes. For example, the federal government may place a lien on a homeowner’s home or other real property for unpaid federal income taxes, and state and local governments (often counties) may place a lien on real property for unpaid income or property taxes.

The federal, state, or local government entity—also known as a taxing authority—may seek to recover payment for unpaid taxes by forcing the sale of the property on which the lien is placed in the foreclosure process—a process in which the validity of the lien and satisfaction (payment) for the lien is litigated or determined in court.

In New York, a property tax lien is a legal claim against a property for unpaid property taxes. This lien has priority over most other liens or claims on the property, including mortgages. When property taxes are delinquent, the taxing authority, which is typically the county in New York, may place a lien on the property. If the taxes remain unpaid, the taxing authority can enforce the lien by selling the property at a tax lien sale or initiating a foreclosure process. During a tax lien sale, investors can purchase the lien and the right to collect the unpaid taxes plus interest. If the property owner fails to pay the taxes, interest, and other costs before the expiration of the redemption period, the lienholder can initiate foreclosure proceedings to take ownership of the property. The foreclosure process involves court proceedings to ensure the validity of the lien and to provide a mechanism for the payment of the lien. It's important for property owners to address tax liens promptly to avoid potential foreclosure and loss of property.