How Are Property Taxes Calculated?

Property taxes are not based on a single number. Instead, they are calculated using your property's value, state-mandated adjustments, and the budgets of local taxing authorities.

The Five Steps of Property Tax

  1. Property Valuation: The County Assessor estimates your property's value every two years (on odd-numbered years). Because the process takes time, you won't pay taxes on a new valuation for about 18 months.
  2. The "Rollback" (Taxable Value): To help with inflation, the State of Iowa applies a "rollback" percentage. This reduces the portion of your property's value that can actually be taxed.
  3. Setting Tax Rates: Local groups (City, Schools, County, Transit) set their own budgets. These budgets determine the "tax rate" per $1,000 of taxable value.
  4. Combining Rates: The County Auditor adds all these individual rates together to create one Consolidated Tax Rate.
  5. Subtracting Credits: Finally, any credits you have applied for (like the Homestead Credit) are subtracted from your total bill.

The Simple Formula

We follow this math to find your total bill:

(Total Value × Rollback Rate) ÷ 1,000 × Consolidated Tax Rate − Credits = Your Total Tax

Example Calculation

This example shows how a typical $200,000 home might be taxed:

Example Calculation for a $200,000 Home
Step Calculation Result
1. Find Taxable Value $200,000 (Value) × 47.4316% (Rollback) $94,863.20
2. Apply Tax Rate ($94,863.20 ÷ 1,000) × $34.12 (Tax Rate) $3,236.78 (Gross Tax)
3. Subtract Credits $3,236.78 − $52.38 (Homestead Credit) $3,184.40 (Total Owed)

Questions?

If you need help calculating your taxes, contact the Finance Department: