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Updated 2025 Tax Year

St. Charles County
Property Tax Guide

Everything you need to know about property taxes in St. Charles 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
0.8%-1.2% of assessed value (varies by special taxing districts), county levy 0.0821%
1st Due
Dec 31
2nd Due
Jun 30
Exemptions
5+ Available
Section 1

How Property Tax Works

St. Charles County property taxes fund essential local services including schools, fire protection, libraries, parks, and county operations. Property owners pay taxes based on their property's assessed value multiplied by the applicable tax rate for their specific location within the county.

The effective property tax rate in St. Charles County varies significantly by location due to overlapping special taxing districts such as school districts, fire districts, ambulance districts, and municipal bonds. While the county's general revenue levy is 0.0821%, total combined rates typically range from approximately 0.8% to 1.2% of assessed value depending on which special districts serve your property. Property assessments are conducted every two years, with real property assessed at 19% of true market value for residential properties.

Section 2

What Makes Up Your Tax Bill

ComponentRateDescription
St. Charles County General Revenue0.0821%Basic county operations and services
School DistrictsVariesLocal school district operating and debt service levies
Fire Protection DistrictsVariesFire and emergency services
Ambulance DistrictsVariesEmergency medical services
Library DistrictsVariesPublic library operations
Municipal BondsVariesVoter-approved bond issues
Special Road DistrictsVariesRoad maintenance and improvements

Rates shown are for Levy Year 2025. Total combined rates vary by property location within St. Charles County due to different combinations of special taxing districts. Contact the St. Charles County Assessor's office at (636) 949-7438 for your specific district combination and current rates.

Section 3

When Are Property Taxes Due?

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

First Installment
Dec 31
Delinquent after Dec 10
Second Installment
Jun 30
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 property taxes in St. Charles County are typically triggered by new construction, property improvements, or changes in property ownership that occur after the annual assessment date. When improvements are completed or ownership transfers happen mid-year, a supplemental assessment may be issued to capture the change in property value for the remainder of the tax year.

The supplemental tax is calculated by determining the difference between the old assessed value and the new assessed value, then applying the current tax rate to that difference, prorated for the remaining months in the tax year. For example, if a $100,000 home improvement is completed in July and assessed at 19% ($19,000 assessed value increase) with a combined tax rate of 1.0%, the supplemental tax would be approximately $95 for the remaining 6 months of that tax year ($19,000 × 1.0% × 6/12 months).

Example Calculation

Example 1: $300,000 Home

  • Market Value: $300,000
  • Assessed Value (19%): $57,000
  • Less: Senior Freeze Credit (if applicable): -$500
  • Net Taxable Value: $56,500
  • Annual Tax (1.0% rate): $565
  • Monthly Escrow: $47

Example 2: $600,000 Home

  • Market Value: $600,000
  • Assessed Value (19%): $114,000
  • Less: Homestead Preservation Credit (if applicable): -$1,000
  • Net Taxable Value: $113,000
  • Annual Tax (1.0% rate): $1,130
  • Monthly Escrow: $94

Example 3: $1,000,000 Home

  • Market Value: $1,000,000
  • Assessed Value (19%): $190,000
  • Credits Applied: Minimal at this value level
  • Net Taxable Value: $190,000
  • Annual Tax (1.1% rate): $2,090
  • Monthly Escrow: $174

Note: Tax credits shown require annual application and income/age qualification. Actual rates vary by special district combination.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in St. Charles County collect property taxes through monthly escrow payments as part of your mortgage payment. Lenders typically collect 1/12th of your annual property tax bill each month, plus a cushion amount allowed by federal law. The lender pays your property taxes directly to St. Charles County when due.

Property taxes in St. Charles County are due in two installments: the first half by May 15th and the second half by October 15th each year. Your lender should make these payments on time, but it's wise to verify through the St. Charles County Collector's online portal. If you pay your own taxes (no escrow), you can pay online at stcharlescountymo.gov, by mail, or in person. After payoff or if you don't escrow, you'll receive tax bills directly and are responsible for timely payment to avoid penalties and interest charges.

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Section 6

Frequently Asked Questions

Q: When are property taxes due for the current fiscal year? A: Property taxes are due in two installments - first half by May 15th and second half by October 15th each year.

Q: What tax credits are available and do I need to apply? A: Available tax credits include the Senior Citizens Property Tax Credit (age 65+ with income limits), Disabled Persons Credit, and various homestead preservation credits. All credits require annual application and are NOT automatic - contact the St. Charles County Assessor at (636) 949-7438 for applications and deadlines.

Q: How does the Homestead Credit work? A: The Homestead Credit caps the annual increase in your property's assessed value growth, not the market value itself. This credit requires annual application and has income limitations. It limits assessment increases rather than providing a flat reduction.

Q: When are properties reassessed? A: St. Charles County conducts property reassessments every two years. Residential properties are assessed at 19% of true market value. You'll receive a notice of any assessment changes with appeal instructions and deadlines.

Q: What are the penalties for late payment? A: Late payments incur interest charges and penalties. After October 15th, unpaid taxes begin accruing interest monthly. Properties with delinquent taxes may eventually face tax sale procedures.

Q: Can I pay my property taxes online? A: Yes, you can pay online at the St. Charles County Collector's website (stcharlescountymo.gov), by phone, mail, or in person at the Collector's office.

Q: Why did my tax bill increase if my assessment stayed the same? A: Tax increases can occur due to higher tax rates from local jurisdictions (school districts, fire districts, etc.) even if your assessed value remains unchanged. Voter-approved bond issues and levy increases affect your total rate.

Q: How do I find out which special taxing districts apply to my property? A: Contact the St. Charles County Assessor's office at (636) 949-7438 or check your property tax statement, which lists all applicable taxing jurisdictions and their respective rates for your specific property location.

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. Charlesauditor.mo.gov
02
State
2025 Property Tax Rate Report - Missouri State Auditor's Officeauditor.mo.gov
03
Tax Doc
Sales and Use Tax Rate Tablesdor.mo.gov
04
Tax Doc
2026 Tax Calendar - Missouri Department of Revenuedor.mo.gov
05
Collector of Revenue Calendarstlouis-mo.gov
06
Frequently Asked Questions - CivicPlus.CMS.FAQstcharlescitymo.gov
07
County
St Charles County Property Taxnacdashboard.nara.gov
08
Homestead exemptionsenate.mo.gov
09
saint charles, mostcharlescitymo.gov
10
County
Sales and Property Tax Rate Information | St Charles County, MO - Official Websitesccmo.org
All sources verified as of 2025 Tax Year

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