How can you add someone to your property deed without having your property taxes reassessed?

Almost every answer in the law section should begin with "It depends on what state you are in," and this one is no different. Most states (or counties) do not automatically reassess property values when property is transferred. Actually, most counties only have the resources to perform an individual assessment of propery when it gets improved (you get a building permit) or when there is a special need (like if you file a dispute over the value of property) Your property will probably be reassessed with everone else's property every few years (5-8) when there is a county wide assessment. So the answer is that you probably won't cause your property to be reassessed by transferring it to someone else.