What is the difference between tax assessed value and market value?  This is one of those issues that confuse many buyers and sellers.   Tax assessed value and market value are not the same.  The tax value can be lower or higher than the market value.   If the tax assessed value is higher than the suggested list price, a seller might reference it to support why he feels his house is worth more.  If the tax assessed value is lower than the list price, a buyer might reference it to support why he feels the house is worth less.  Neither would be correct.

The true value of a property is determined by its market value.  Market value is the highest price likely to be paid for a property, assuming that the property was available to all potential buyers at a realistic price or a reasonable length of time.  Additionally, neither buyer nor seller was prevented from learning all of the facts about the property and its place in the market.  Tax assessed value is determined by most counties using some complicated math formula that re-appraises all the properties in the county at one time.  Moreover, there is inconsistency among properties assessed by the tax assessor because many homeowners protest their taxes in the Spring to keep their taxes low. In those cases this result in a different value being placed on their properties and that of their neighbors with similar homes.

The most common approach to property value is Market Analysis or Comparable Approach.  Both determine prices paid for similar properties in the neighborhood by analyzing recently sold properties.  Recently sold is any property closed preferably within the last six months in the same neighborhood, typically within 1/4 to 1/2 mile from the subject property.  The Tax assessor's office doesn't have access to comparable sales that are MLS(Multiple Listing Service) to determine your property's true market value.  Therefore, the tax assessed value should never be assumed to mean market value.