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Updated 2025 Tax Year

St. Louis County
Property Tax Guide

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

10 Official Sources
8 min read
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Quick Facts
Tax Rate
Approximately $0.2630 per $100 of assessed valuation (varies by taxing district)
1st Due
Dec 31
2nd Due
Jan 31
Exemptions
5+ Available
Section 1

How Property Tax Works

St. Louis County operates under Missouri's property tax system, where property taxes serve as a crucial funding source for local government services, school districts, fire protection districts, and other special taxing districts. Property owners in St. Louis County pay taxes based on their property's assessed value, which is determined by the County Assessor's Office and reassessed periodically to reflect current market conditions.

The effective property tax rate in St. Louis County is approximately $0.2630 per $100 of assessed valuation, though the total rate varies depending on the specific taxing districts where your property is located. Missouri assesses residential property at 19% of its true value in money, meaning a home valued at $300,000 would have an assessed value of $57,000. These taxes fund essential services including public schools, county operations, municipal services, library systems, and emergency services throughout St. Louis County.

Section 2

What Makes Up Your Tax Bill

ComponentRate per $100 Assessed ValueDescription
County GeneralVaries by districtBasic county services, roads, courts, sheriff
School DistrictVaries by districtLocal school district operations and debt service
MunicipalVaries by cityCity services, police, fire, parks
Fire ProtectionVaries by districtFire and emergency medical services
Library DistrictVaries by districtPublic library system operations
Special DistrictsVaries by districtWater, sewer, lighting, or improvement districts
Total Composite Rate~$0.2630Combined rate for all applicable districts

Note: The exact rate depends on which taxing jurisdictions your property falls within. Properties may be subject to additional special assessments or Community Improvement Districts (CIDs).

Section 3

When Are Property Taxes Due?

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

First Installment
Dec 31
Delinquent after Dec 10
Second Installment
Jan 31
Delinquent after Apr 10
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. Louis County are additional property tax assessments that occur when there are changes to property ownership, value, or improvements outside the regular assessment cycle. The most common triggers include new construction completion, major renovations that increase property value, or when the County Assessor discovers previously unassessed improvements to a property.

These supplemental assessments are calculated using the same tax rate structure as regular property taxes, but they're prorated based on the remaining months in the tax year when the change occurred. For example, if a home addition valued at $50,000 (assessed at $9,500) is completed in July, the owner would pay supplemental taxes for the remaining 6 months of that tax year. Using the county's rate of $0.2630 per $100 assessed value, this would result in a supplemental tax bill of approximately $12.49 ($9,500 ÷ 100 × $0.2630 ÷ 2).

Example Calculation

$300,000 Property Value

  • Market Value: $300,000
  • Assessed Value (19%): $57,000
  • Less Homestead Exemption: Check with assessor
  • Net Taxable Assessed Value: ~$57,000
  • Annual Tax ($57,000 ÷ 100 × $0.2630): $149.91
  • Monthly Escrow: $12.49

$600,000 Property Value

  • Market Value: $600,000
  • Assessed Value (19%): $114,000
  • Less Homestead Exemption: Check with assessor
  • Net Taxable Assessed Value: ~$114,000
  • Annual Tax ($114,000 ÷ 100 × $0.2630): $299.82
  • Monthly Escrow: $24.99

$1,000,000 Property Value

  • Market Value: $1,000,000
  • Assessed Value (19%): $190,000
  • Less Homestead Exemption: Check with assessor
  • Net Taxable Assessed Value: ~$190,000
  • Annual Tax ($190,000 ÷ 100 × $0.2630): $499.70
  • Monthly Escrow: $41.64

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Section 5

Escrow & Property Taxes

Most mortgage lenders in St. Louis County require borrowers to maintain an escrow account for property tax payments, especially when the loan-to-value ratio exceeds 80%. Your lender collects monthly escrow payments along with your mortgage payment, then pays your property taxes directly to St. Louis County when they become due on December 31st each year. The monthly escrow amount is calculated by taking your annual tax bill, adding a small cushion (typically 2 months), and dividing by 12.

Lenders are required to provide an annual escrow analysis showing how your funds were used and whether adjustments to your monthly payment are needed. Since St. Louis County must mail property tax statements to resident taxpayers by October 26th, you should receive notification of any tax changes well before the December 31st due date. If you pay your own taxes (without escrow), you're responsible for ensuring timely payment to avoid penalties and interest charges that accrue after the December 31st deadline.

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. Louis County? A: Property taxes are due by December 31st each year. Payments received after December 31st are subject to penalties and interest.

Q: What homestead exemptions are available? A: Missouri's constitution provides for homestead exemptions for qualifying citizens. Contact the St. Louis County Assessor's Office to determine your eligibility and application requirements.

Q: How often are properties reassessed? A: St. Louis County conducts periodic reassessments to ensure assessed values reflect current market conditions. The County Assessor's Office determines the reassessment schedule.

Q: When do I receive my property tax assessment notice? A: Assessment notices are typically mailed between May 1-15, with the final deadline for the Assessor to deliver value notices being June 15th.

Q: How do I appeal my property tax assessment? A: Informal appeals begin May 1st each year. Contact the St. Louis County Assessor's Office for specific procedures and deadlines for filing an appeal.

Q: When are personal property declarations due? A: Personal property declaration forms are mailed February 1st and must be returned by April 1st (previously referenced as March 1st in some sources - verify current deadline).

Q: Can I pay my property taxes online? A: Contact the St. Louis County Collector's Office for current online payment options and accepted payment methods.

Q: What happens if I pay my taxes late? A: Late payments incur penalties and interest charges. The exact penalty structure can be obtained from the St. Louis County Collector's Office.

Q: Who do I contact with questions about my tax bill? A: For assessment questions, contact the St. Louis County Assessor's Office. For payment questions, contact the St. Louis County Collector's Office.

Q: What if I disagree with a supplemental tax assessment? A: Supplemental assessments can typically be appealed through the same process as regular assessments. Contact the Assessor's Office for specific procedures and deadlines.

Verified Sources

Backed by 10 Official Government Sources

Every fact in this guide is sourced from official county, state, and federal documents.

01
County
Tax Rates for County: St. Louis Cityauditor.mo.gov
02
Tax Doc
2025 Property Tax Rates for City of St Louisstlouis-mo.gov
03
County
St. Louis County Real & Personal Property Tax Rateseureka.mo.us
04
State
Appeal Dates and Deadlines - Real Estatestlouis-mo.gov
05
File Personal Property Declarationstlouiscountymo.gov
06
Tax Doc
Delinquent Property Tax Informationstlouiscountymo.gov
07
Tax Doc
DISABLED POW REAL PROPERTY TAX EXEMPTIONstlouiscountymo.gov
08
Property Exemptionsstlouiscountymo.gov
09
Homestead exemptionsenate.mo.gov
10
Tax Doc
Modifies several provisions of law concerning taxation ...senate.mo.gov
All sources verified as of 2025 Tax Year

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