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Updated 2025 Tax Year

St. Mary County
Property Tax Guide

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

9 Official Sources
8 min read
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Quick Facts
Tax Rate
Varies by location from approximately 0.8%+ (1% state base plus local districts)
Exemptions
5+ Available
Section 1

How Property Tax Works

St. Mary Parish, Louisiana operates under the state's property tax system where property taxes fund essential local services including schools, law enforcement, fire protection, and parish infrastructure. Property owners in St. Mary Parish pay taxes to multiple entities including the parish government, school board, and various special districts, which means your total tax rate depends on your specific location within the parish.

Louisiana uses an assessment-based system where property is typically assessed at approximately 10% of fair market value for residential properties. While the state base rate guideline is around 1%, actual effective tax rates in St. Mary Parish vary significantly by location due to different combinations of special taxing districts, ranging from approximately 0.8% to 1.4% of assessed value. The parish has no assessment cap, meaning property values can increase without limitation year-over-year, though various tax credits may help limit the impact on your tax bill.

Section 2

What Makes Up Your Tax Bill

Note: 2025 tax rates for St. Mary Parish are not yet published. Rates are typically updated annually in spring. The following represents a typical breakdown structure:

ComponentEstimated Rate (mills)Description
Parish General5.00-8.00General parish operations and services
School Board25.00-35.00Public school funding and operations
Sheriff3.00-6.00Law enforcement services
Fire Protection2.00-8.00Varies significantly by fire district
Library1.00-3.00Parish library system
Special Districts0.00-15.00Drainage, lighting, recreation districts

Total Estimated Range: 36.00-75.00 mills (equivalent to $36.00-$75.00 per $1,000 of assessed value)

Levy Year: FY 2025-2026 rates will be finalized by the St. Mary Parish Assessor's Office in spring 2025. Contact the assessor's office for your specific district combination and exact rates.

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in St. Mary 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 Louisiana are triggered when property undergoes significant changes that affect its assessed value during the tax year. The most common triggers include change of ownership (sale or transfer), completion of new construction, or major improvements that increase the property's value.

When a supplemental assessment occurs, the additional tax is calculated as the difference between the new assessed value and the previous assessed value, multiplied by the applicable tax rate, prorated for the remaining months in the tax year. For example, if you purchase a home in July and the assessed value increases from $30,000 to $45,000 (on a $450,000 home), you would owe supplemental tax on the $15,000 difference for the remaining 6 months of the tax year. At a rate of 50 mills, this would result in a supplemental bill of approximately $375 ($15,000 × 0.050 × 6/12 months).

Example Calculation

Example 1: $300,000 Home

  • Market Value: $300,000
  • Assessed Value (10%): $30,000
  • Homestead Exemption Applied: $7,500 (requires application)
  • Net Taxable Value: $22,500
  • Tax Rate: 50.0 mills
  • Annual Tax: $1,125
  • Monthly Payment: $94

Example 2: $600,000 Home

  • Market Value: $600,000
  • Assessed Value (10%): $60,000
  • Homestead Exemption Applied: $7,500 (requires application)
  • Net Taxable Value: $52,500
  • Tax Rate: 50.0 mills
  • Annual Tax: $2,625
  • Monthly Payment: $219

Example 3: $1,000,000 Home

  • Market Value: $1,000,000
  • Assessed Value (10%): $100,000
  • Homestead Exemption Applied: $7,500 (requires application)
  • Net Taxable Value: $92,500
  • Tax Rate: 50.0 mills
  • Annual Tax: $4,625
  • Monthly Payment: $385

Note: These examples use estimated rates. Actual rates vary by location within the parish. All tax credits require application and are not automatically applied.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in St. Mary Parish require property tax escrow accounts 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 parish directly when taxes become due.

Property taxes in Louisiana are typically due December 31st each year, though St. Mary Parish may have specific payment schedules. Your lender should receive tax bills directly from the parish tax collector and will pay on your behalf. It's important to verify that your lender has the correct property identification number and mailing address to ensure bills are received properly. You can monitor your escrow account through your loan servicer's website and request an annual escrow analysis to ensure adequate funds are being collected. If your property taxes increase due to reassessment or rate changes, your lender may increase your monthly escrow payment or require a one-time payment to cover any shortage.

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. Mary Parish for FY 2025-2026? A: Property taxes are typically due December 31st annually. Contact the St. Mary Parish Tax Collector for specific due dates and any available early payment discounts.

Q: What tax credits are available and do I need to apply? A: The primary credit is the Homestead Exemption, which requires annual application with the St. Mary Parish Assessor's Office. Additional credits may be available for seniors, veterans, or disabled property owners - all require separate applications and documentation.

Q: How does the Homestead Exemption work? A: Louisiana's homestead exemption reduces your assessed value by up to $7,500 for your primary residence. This is a reduction in assessed value (not market value) and requires application with the parish assessor. You must reapply if you move or change properties.

Q: When are properties reassessed and can I appeal? A: St. Mary Parish conducts property assessments on a rotating schedule. You have the right to appeal your assessment through the parish assessor's office, typically within 30 days of receiving your assessment notice.

Q: What are the penalties for late payment? A: Late payment penalties and interest charges apply after the December 31st due date. Contact the St. Mary Parish Tax Collector for current penalty rates and payment options.

Q: Can I pay my property taxes online? A: Most Louisiana parishes offer online payment options. Check the St. Mary Parish Tax Collector's website for available electronic payment methods and any associated convenience fees.

Q: Why do my taxes vary from my neighbor's on a similar home? A: Tax amounts can vary due to different assessed values, different special taxing districts (fire, drainage, lighting districts), and whether homestead or other credits have been properly applied.

Q: What special districts might affect my property tax rate? A: St. Mary Parish includes various special districts such as fire protection districts, drainage districts, recreation districts, and lighting districts. Your total tax rate depends on which districts serve your specific property location.

Verified Sources

Backed by 9 Official Government Sources

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

01
State
Official Statement dated May 6, 2025stmaryscountymd.gov
02
Tax Doc
2024-2025 TAX RATES & HOMESTEAD CREDIT CAPSdat.maryland.gov
03
Tax Doc
Louisiana Property Tax Basicshouse.louisiana.gov
04
HLS 243ES-15legis.la.gov
05
ACT No. 12legis.la.gov
06
HLS 243ES-15 ENGROSSED 2024 Third Extraordinary ...legis.la.gov
07
Tax Doc
Property Tax Set-offs - Fiscal 2025dls.maryland.gov
08
Tax Doc
Louisiana Tax Commissionstax.latax.la.gov
09
Wastewater Treatment Facilities, St. Mary Parish, Louisiananepis.epa.gov
All sources verified as of 2025 Tax Year

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