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Updated 2025 Tax Year

St. Clair County
Property Tax Guide

Everything you need to know about property taxes in St. Clair County, AL. Rates, due dates, exemptions, and how it affects your monthly payment.

10 Official Sources
8 min read
Quick Facts
Tax Rate
40-60 mills (4.0-6.0% of assessed value) - varies by location and special districts
Exemptions
4+ Available
Section 1

How Property Tax Works

St. Clair County, Alabama operates under a property tax system that funds essential local services including schools, county government operations, infrastructure maintenance, and emergency services. Property taxes are assessed based on the fair market value of real estate and personal property, with the state assessment ratio of approximately 10% for residential properties and 20% for commercial properties.

The effective property tax rates in St. Clair County vary significantly by location within the county due to special taxing districts, municipal boundaries, and school district overlays. Property owners can expect total millage rates ranging from approximately 40-60 mills (4.0% to 6.0% of assessed value), depending on their specific location and applicable special assessments. The state portion is set at 6.5 mills, while county, municipal, and school district rates vary by jurisdiction within St. Clair County.

Section 2

What Makes Up Your Tax Bill

ComponentRate (Mills)Description
State Tax6.5Fixed state property tax rate
County GeneralVariesSt. Clair County general fund operations
School DistrictVariesLocal school district funding (varies by district)
MunicipalVariesCity/town taxes (if applicable to property location)
Special DistrictsVariesFire districts, library districts, other special assessments
Total Range40-60Combined millage varies by specific location

Note: These rates apply to the current tax year and are subject to annual adjustment by each taxing authority. Rates shown are estimates as exact millage rates vary by specific taxing jurisdiction within St. Clair County. Contact the St. Clair County Revenue Commissioner for precise rates applicable to your property location.

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in St. Clair County, property taxes are due in two installments:

Pro tip: If you pay through mortgage escrow, your lender splits these payments across your monthly mortgage. If you pay directly, set calendar reminders to avoid late penalties.
Section 4

Supplemental Tax Bills

Supplemental taxes in St. Clair County are additional property tax assessments that occur when there are changes in property ownership, new construction, or improvements that increase a property's assessed value during the tax year. These taxes are calculated based on the difference between the old and new assessed values, prorated for the remaining months in the tax year.

Common triggers include: purchasing a home that hasn't been reassessed recently, completing major home improvements or additions, new construction reaching occupancy, or correction of assessment errors. For example, if you complete a $50,000 home addition in June and your assessment increases by $5,000 (10% of improvement value), you would owe supplemental taxes on that $5,000 increase for the remaining 7 months of the tax year at your property's applicable millage rate.

Example Calculation

Example 1: $300,000 Home Value

  • Market Value: $300,000
  • Assessed Value (10%): $30,000
  • Less: Homestead Credit (if applied): $4,000
  • Net Taxable Value: $26,000
  • Annual Tax (50 mills): $1,300
  • Monthly Escrow: $108

Example 2: $600,000 Home Value

  • Market Value: $600,000
  • Assessed Value (10%): $60,000
  • Less: Homestead Credit (if applied): $4,000
  • Net Taxable Value: $56,000
  • Annual Tax (50 mills): $2,800
  • Monthly Escrow: $233

Example 3: $1,000,000 Home Value

  • Market Value: $1,000,000
  • Assessed Value (10%): $100,000
  • Less: Senior Credit (if qualified and applied): $2,000
  • Net Taxable Value: $98,000
  • Annual Tax (50 mills): $4,900
  • Monthly Escrow: $408

Note: Tax credits require application and approval. Millage rate of 50 mills used for illustration - actual rates vary by location within St. Clair County.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in St. Clair County require borrowers to maintain an escrow account for property tax payments, especially for loans with less than 20% down payment. Your lender collects 1/12 of your estimated annual property tax bill each month along with your mortgage payment, then pays the St. Clair County Revenue Commissioner directly when taxes become due on October 1st.

Lenders typically maintain a cushion of 2-6 months of tax payments in your escrow account and conduct annual escrow analyses to adjust your monthly payment based on actual tax bills and account balance. You'll receive an escrow statement showing payments made on your behalf and any adjustments needed for the coming year. If your property taxes increase due to reassessment or rate changes, your monthly mortgage payment will be adjusted accordingly. Property owners can verify that their taxes were paid correctly by checking with the St. Clair County Revenue Commissioner's office or through online payment portals.

How HonestCasa Helps
  • Understand whether your escrow is set correctly
  • See how rising taxes will change your monthly payment
  • Plan ahead instead of being surprised by "shortage" letters
Section 6

Frequently Asked Questions

Q: When are property taxes due in St. Clair County? A: Property taxes are due October 1st each year and become delinquent after December 31st. Late payments are subject to penalties and interest charges.

Q: What homestead tax credits are available and how do I apply? A: The primary homestead credit caps annual assessment increases and provides exemptions for qualifying homeowners. Senior citizens age 65+ may qualify for additional credits with income restrictions ($12,000 adjusted gross income limit). All credits require application through the St. Clair County Assessor's office and are NOT automatic.

Q: How does the homestead credit work? A: The homestead credit doesn't reduce your home's market value, but it can limit how much your assessed value increases each year and provide exemption amounts. You must file an application with the County Assessor to receive this benefit - it is not automatically applied.

Q: How often are properties reassessed in St. Clair County? A: Alabama requires property reassessment every four years, though properties may be reassessed more frequently due to sales, improvements, or appeals. The most recent countywide reassessment cycle should be verified with the County Assessor.

Q: How do I appeal my property assessment? A: Assessment appeals must be filed with the St. Clair County Board of Equalization within specific deadlines after receiving your assessment notice. Contact the County Assessor's office for appeal forms and procedures.

Q: What are the penalties for late property tax payments? A: Properties with unpaid taxes after December 31st are subject to penalties, interest, and potential tax sale proceedings. Contact the Revenue Commissioner's office for specific penalty rates and collection procedures.

Q: Can I pay my property taxes online? A: Check with the St. Clair County Revenue Commissioner's office for available online payment options and accepted payment methods. Many Alabama counties now offer online tax payment systems.

Q: Why did I receive a supplemental tax bill? A: Supplemental taxes occur when your property's assessed value changes during the tax year due to new construction, improvements, ownership changes, or assessment corrections. You're billed for the additional tax amount prorated for the remaining months in the tax year.

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