Prorated property tax calculator

How the property tax proration works

Adjusted tax = period tax × contract percentage ÷ 100. Seller’s share = adjusted tax × seller days ÷ total days. Buyer’s share is the remainder. This worksheet uses actual calendar days, including February 29 in a leap year.

Use the period the tax covers, which may differ from the year payment is due. This worksheet assumes one party pays the full period’s bill. For partial payments, multiple bills, a 30-day-month convention or a reproration agreement, ask your closing agent for a settlement calculation.

For illustration, a $3,650 bill for a 365-day period means $10 per day at 100%. A seller with 100 days has a $1,000 share; the buyer’s share is $2,650. These are hypothetical inputs.

Check the contract before using a credit

Illinois guidance describes a seller credit for the period before closing, subject to the real estate contract. Confirm the allocation in your agreement.

This Illinois guidance is a state example, not a national closing rule. The owner of closing day and the percentage above are worksheet assumptions; confirm both in your agreement. This does not estimate a buyer’s future assessment or supplemental tax.