Your property taxes are based on the market value of your home, or more simply, what you could currently sell your home for. Your town (or county, in the case of Nassau) is responsible for assessing all homes in your region, including yours.
The problem is that the assessment of your home’s value may be incorrect. Real estate values have gone down, and homes are being sold for less. With this reality, it’s likely that you could be paying more property taxes than you should.
The only way to reduce the amount you pay in property taxes is to lower your assessment. You do this by filing a grievance with your local assessor’s office. You can do it yourself, or you can hire an experienced professional to represent you. Either way, the important thing to remember is that you must file a grievance to lower your taxes.