Property Tax Proration CalculatorFree online financial calculator — instant results, no sign-up
Allocate an annual property tax bill using an explicit day count convention.
Estimates only, based on the inputs and assumptions shown. This is not financial, investment, tax, or legal advice. Prices, rates and local rules may change; crypto scenarios do not predict returns. Confirm important decisions with a qualified professional.
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About the Property Tax Proration Calculator
The Property Tax Proration Calculator divides an annual property tax bill between a seller and buyer using the seller’s responsibility days and an explicitly entered tax-year day count. It calculates the seller’s proportional share and assigns the remaining tax amount to the buyer. Use day counts that match the purchase contract or closing instructions.
- Annual property tax ($)
- The total property tax bill to allocate for the tax year, in dollars, with a default of $6,000.
- Seller responsibility (days)
- The number of days allocated to the seller under the agreed proration convention, in days, with a default of 140.
- Days in tax year (days)
- The total number of days used as the proration denominator for the tax year, in days, with a default of 365.
Formula and method
S = round(T × d / D, 2); B = T − S.
- TAnnual property tax in dollars.
- dSeller responsibility in days.
- DTotal days in the tax year under the selected convention.
- SSeller share in dollars, rounded to the nearest cent.
- BBuyer share in dollars, calculated as the remaining annual tax.
- round(x, 2)Round the amount x to two decimal places.
Divide the seller’s responsibility days by the tax-year day count, then multiply that fraction by the annual property tax. Round the seller’s share to cents and subtract it from the annual bill to obtain the buyer’s share. With the default inputs, S = round($6,000 × 140 / 365, 2) = $2,301.37, and B = $6,000 − $2,301.37 = $3,698.63. Keep full precision until rounding the seller’s share rather than rounding a daily tax rate first.
Worked example
These are the calculator's starting values and the results it actually produces for them.
Inputs
- Annual property tax6000 $
- Seller responsibility140 days
- Days in tax year365 days
Results
- Seller share$2,301.37
- Buyer share$3,698.63
How to use the Property Tax Proration Calculator
- 1Enter the annual property tax bill in dollars; the default is $6,000.
- 2Confirm the applicable tax period and whether the closing day belongs to the seller or buyer under the closing instructions.
- 3Enter the seller’s responsibility days for that period; the default is 140 days.
- 4Enter the matching tax-year day count; the default is 365 days, and the seller’s days must be between zero and this total.
- 5Calculate and review the seller and buyer shares, then compare the allocation with the closing statement.
Reading your result
The Seller share row shows the portion of the annual tax allocated to the seller: $2,301.37 with the default inputs. The Buyer share row shows the remaining portion allocated to the buyer: $3,698.63. Together, the shares equal the $6,000 annual bill. These amounts describe responsibility for the tax, not necessarily who must pay whom at closing; that depends on whether the bill has already been paid.
Limitations
This calculator assumes property tax accrues evenly across the entered tax-year day count and that the seller and buyer together cover the entire period. It does not derive days from dates, determine who is responsible for the closing day, or automatically select a calendar-year, fiscal-year, leap-year, or contractual convention. The annual tax must be nonnegative, the tax-year day count must be positive, and seller days must fall between zero and the total year days. Estimates, reassessments, exemptions, supplemental bills, penalties, and local closing rules may change the final allocation. Settlement systems that round intermediate values differently may produce a small rounding difference.
Common questions
Does the seller’s day count include the closing day?+
Only if the purchase contract or applicable closing instructions assign that day to the seller. This calculator accepts your entered count and does not decide ownership of the closing day.
Should I change the tax-year day count for a leap year?+
If your agreement uses actual days and the applicable tax period includes a leap day, use the actual number of days in that period. If the agreement specifies a fixed denominator, use that denominator and count seller days consistently with that convention.
Why is the buyer’s share calculated by subtraction?+
Subtracting the rounded seller share from the annual bill keeps the two allocations equal to the bill. With the defaults, $6,000 minus $2,301.37 leaves the buyer share of $3,698.63.
Does the seller share become a credit to the buyer at closing?+
If the buyer will pay an unpaid tax bill covering both parties’ responsibility periods, the seller’s allocated share is commonly credited to the buyer. If the seller has prepaid the bill, the buyer commonly reimburses the seller for the buyer’s allocated portion. Confirm the actual treatment in the closing statement.
Does the calculator save my information?+
Calculations run in your browser. While signed in, inputs and results are automatically recorded in account history; saving a result creates a separate saved record.
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Results are estimates for informational purposes and are not financial, medical or legal advice.