That is a question I hear quite a bit. Understandably so.
Depending on where you live, property taxes might be a big deal
Here in Central PA, part of the taxes a homeowner pays (property tax) goes to the local government and part of it goes to the school district.
There has been talk about reducing or eliminating school tax from the burden of homeowners. There are strong arguments for AND against that idea. I won't get into that here. Let's talk about your tax assessment value.
For now, we pay taxes on property we own. The amount we pay is based on the assessed value of the home. Where I live (York County) it is the Department of Assessment that determines the assessed value. Every county is different, so check with your local government for details. Or call me and I'll find out for you!
Back to the original question: What if you disagree with their value?
For those of you living in York County, you would need to file an appeal. You have to use their official form and provide proof showing why the current assessment is wrong. The information on doing that is on the York County website.
It's a fine line. When selling your home, you may want the assessed value to be as much as possible. For tax purposes, most people would rather that number be lower.
I would suggest that before filing an appeal or calling an appraiser, call a Realtor. They don't all do this service, but I will for my clients. I can give you my opinion of the fair market value. Maybe your home is worth MORE than you think. It happens, and that isn't necessarily a bad thing :-)