Property tax in St. Mary Parish, Louisiana
The median property tax bill in St. Mary Parish, Louisiana is $545 a year, which is about 0.39% of the county's median home value of $138,900. That effective rate is lower than the typical Louisiana county (0.43%) and lower than the national median (0.81%). These are American Community Survey 5-year estimates (2024); your own bill depends on your home's assessed value and any exemptions.
Estimate the property tax on a home in St. Mary Parish
Enter a home's market value for a ballpark at St. Mary Parish's average effective rate of 0.39% (Census). The real bill depends on the home's assessed value, the millage where it sits and any exemptions.
Estimated property tax: $542 / year
Property tax in St. Mary Parish at a glance
| Measure | Value |
|---|---|
| Median annual property tax | $545 |
| Median home value | $138,900 |
| Effective tax rate | 0.39% |
| Typical Louisiana county rate | 0.43% |
| National median county rate | 0.81% |
Effective rate = median real estate taxes paid divided by median home value. Source: U.S. Census Bureau, American Community Survey 5-year estimates.
How does St. Mary Parish compare in Louisiana?
Among Louisiana's 64 counties, St. Mary Parish has the 37th highest effective property-tax rate: 36 rank higher and 27 rank lower. That is near the middle for Louisiana. Nationally, it ranks 2947th of 3135 US counties by effective rate. See every Louisiana county ranked.
How much do homeowners in St. Mary Parish actually pay?
The median is only the middle bill. Across St. Mary Parish's 12,673 owner-occupied homes, 5.1% pay $3,000 or more a year in property tax, 8.6% pay at least $2,000, and 45.8% pay under $800. Another 29.9% report paying no property tax at all, which usually means an exemption covers the whole bill.
| Annual bill | Homes | Share |
|---|---|---|
| Under $800 | 5,803 | 45.8% |
| $800 to $1,499 | 1,306 | 10.3% |
| $1,500 to $1,999 | 693 | 5.5% |
| $2,000 to $2,999 | 444 | 3.5% |
| $3,000 or more | 644 | 5.1% |
| No property tax paid | 3,783 | 29.9% |
Owners with a mortgage pay a median of $658 and owners without one pay $447. Owners who have paid off a home have usually held it longer, and in states that cap how fast an existing owner's assessment can rise, long-held homes carry lower assessed values. Census table B25103.
How does the St. Mary Parish property tax bill compare with local incomes?
The median property tax bill of $545 is about 0.8% of the median income of St. Mary Parish homeowner households, $65,596 a year. That compares two middles, so a retiree in a long-held home can pay a far larger share. 68.6% of St. Mary Parish's occupied homes are lived in by their owners; renters pay property tax too, just folded into rent.
Have property taxes gone up in St. Mary Parish?
Yes. The median bill went from $408 in 2015-2019 to $545 in 2020-2024, a 33.6% rise. Over the same span the median home value moved 29.9%, from $106,900 to $138,900.
Two Census ACS 5-year periods with no survey years in common, in each period's own dollars. A change counts only if it exceeds the combined 90% margin of error.
Property tax in counties next to St. Mary Parish
St. Mary Parish borders 4 counties.
| County | Effective rate | Median bill | Median home value |
|---|---|---|---|
| Terrebonne Parish, LA | 0.45% | $836 | $187,200 |
| St. Martin Parish, LA | 0.44% | $725 | $164,200 |
| St. Mary Parish, LA (this county) | 0.39% | $545 | $138,900 |
| Assumption Parish, LA | 0.37% | $552 | $150,300 |
| Iberia Parish, LA | 0.36% | $593 | $164,500 |
How is a home assessed in St. Mary Parish?
Louisiana assesses homes at 10% of market value in every county, St. Mary Parish included. How Louisiana assesses and reappraises homes.
Is there a homestead exemption in St. Mary Parish?
Yes. Louisiana exempts the first $75,000 of market value of an owner-occupied home ($7,500 of assessed value), though it generally does not cover municipal taxes. That is the Louisiana rule, and it applies in St. Mary Parish. Louisiana's exemptions and relief programs in full.
When are property taxes due in St. Mary Parish?
One annual payment, due no later than December 31 and collected by the parish sheriff, or by the City of New Orleans in Orleans Parish. Unpaid taxes are delinquent on January 1 and accrue 1% per month in simple interest, with a 5% penalty added if the lien goes to auction.
That is the Louisiana rule. St. Mary Parish issues and collects the bill, so the dates printed on your statement are the ones that bind you.
How to appeal your St. Mary Parish property assessment
You contest the assessed value with the Parish assessor, then the parish Board of Review, then the Louisiana Tax Commission. The filing deadline is typically varies by parish, within a statutory window. That is the Louisiana rule; St. Mary Parish sets the exact dates and forms. The Louisiana appeal process step by step.
Louisiana rules from primary state sources, reviewed September 7, 2026; sources on the Louisiana page.
Work out your own numbers
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How much house can I afford?
Your income, debts and down payment against the 28/36 rule lenders actually use, with St. Mary Parish's tax rate to hand.
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Mortgage calculator
Monthly payment with principal, interest, tax and insurance, plus what an extra payment saves you.
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Louisiana income tax
Brackets, standard deduction and what Louisiana actually taxes.
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Sales tax in St. Mary Parish
The other local tax: combined state and local rate for this county.
Sources
- Median real estate taxes paid and median home value for St. Mary Parish, Louisiana: U.S. Census Bureau, American Community Survey 5-year estimates (2020-2024), tables B25103, B25077, B25102, B25119 and B25003; the five-year comparison uses the 2015-2019 estimates. Neighboring counties: Census county adjacency file.