Proposition 2 1 / 2 limits the amount the town can raise in local property taxes. The amount that can be raised in any year is equal to:
The amount raised in the previous year, less any overrides or debt exemptions plus
New growth plus
Any overrides or debt exclusions
This limit applies to the total tax levy of the town. It does not apply to individual properties within the town.
The tax due on a specific piece of property is determined by the ratio of the assessed value of that property to the total assessed value of the entire town. That ratio will change as new growth adds to the total assessed value of the town and as improvements add to the value of an individual property.
The ratio will also change in a revaluation year as the relative values of various classes and sub-classes of properties change.
The total amount that may be raised does not depend on the total assessed value of the town. So, for example, if a revaluation of the entire town increases the total assessment of the town by 25%, that increase will have no effect on the total allowable tax for the town.
Massachusetts Department of Local Services Proposition 2 1/2 Video