How will the new valuation affect my tax bill? If my assessment went down, how can my tax bill go up?

Individual assessments may rise or fall depending on characteristics of the property. The purpose of mass appraisal is to value all property by the same standards at the same time to create an equitable distribution of the tax levy. If the same amount of money is to be raised for the current year after a valuation update from the previous year, and each assessment has doubled, the tax rate would be cut in half. And vice versa, if each assessment decreased by 20%, and the same amount of money was to be raised, the tax rate would increase by 20%. Increases or decreases in assessed values do not cause a tax increase or decrease. 

In reality, the tax levy increases each year by 2 1/2 percent per Proposition 2 1/2 and any "new growth" (new constructions, additions, etc.) occurring in the previous year.  If after the Annual Town Meeting, where the expenses of the Town are voted on each year, there is excess levy, the Select Board, through a subsequent Town Meeting, make the determination to tax up to the levy.  *An approved Proposition 2 1/2 override and/or Capital Debt Exclusion will cause an increase in the levy, therefore, increasing tax bills.