Complete a Principal Residence Exemption (PDF) (PRE) - Also know as a "homestead". If you (the new owner) are planning on owning and occupying this home as your principal residence you are exempted from paying 18 mills in school operating taxes. This form must be filed no later than June 1st to have the exemption apply to your Summer Property Taxes. PRE has no effect on your winter taxes
If your new home wasn't owner occupied at the time you purchased it, and you file after June 1st, your summer taxes will not have the Homestead / PRE Exemption on them.
If your new home was occupied by the former owner at the time of sale, the property is considered "homesteaded" for the year. You must still file the paperwork.