Tax proration is the division of property tax responsibility between buyer and seller when property ownership changes during a tax year. Since tax bills typically cover full calendar years but properties may sell mid-year, proration determines what portion each party pays. Lawyers calculate proration based on closing date, allocating responsibility for the portion of the year each party owned the property. If taxes have been prepaid, the buyer reimburses the seller for the post-closing period. If taxes are unpaid, the seller credits the buyer for the pre-closing period. Tax proration is a standard part of real estate closings, ensuring fair allocation and preventing one party from bearing costs for a period they didn't own the property.