St. Mary Parish, LA Demographics
St. Mary Parish, LA is the 22nd most populous of 64 counties in Louisiana, with 49,406 residents across 559 square miles. That is about 88 people per square mile.
At the 2020 census
| Population | 49,406 |
|---|---|
| Land area | 559 sq mi |
| Density | 88 / sq mi |
Data: 2020 Census · American Community Survey 2024
How St. Mary Parish compares to the US
We're computing this county's comparison table — check back shortly. Population, land area, and density above are already exact.
Central Location: St. Mary Parish, LA
Measured from the county's main population center using 2020 census blocks.
We're computing the drive-time and radius areas around St. Mary Parish, LA — check back shortly. Meanwhile you can drop a pin anywhere in the radius tool.
Census tracts in St. Mary Parish, LA
| Name | Population | Sq mi | Per sq mi |
|---|---|---|---|
| Census Tract 405 | 4,806 | 7.5 | 644 |
| Census Tract 408 | 4,773 | 114.1 | 42 |
| Census Tract 402 | 4,738 | 3.3 | 1,425 |
| Census Tract 406 | 4,218 | 6.9 | 614 |
| Census Tract 404 | 3,690 | 0.7 | 5,112 |
| Census Tract 410 | 3,678 | 111.6 | 33 |
| Census Tract 407 | 3,633 | 1.3 | 2,787 |
| Census Tract 414 | 3,142 | 11.8 | 267 |
| Census Tract 403 | 2,912 | 1.8 | 1,583 |
| Census Tract 409 | 2,912 | 159.1 | 18 |
| Census Tract 401 | 2,565 | 29.3 | 88 |
| Census Tract 413 | 1,922 | 3.6 | 534 |
| Census Tract 415 | 1,710 | 1.1 | 1,553 |
| Census Tract 416 | 1,683 | 1.3 | 1,299 |
| Census Tract 412 | 1,546 | 1.7 | 931 |
| Census Tract 411 | 1,478 | 103.5 | 14 |
Related places
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Metro areas containing St. Mary Parish
About this page
This page shows demographics for a US county from the 2020 census and the American Community Survey: population, land area, density, urban share, and how the county compares to national averages for income, housing, age, and more.
Counties subdivide into census tracts, listed below with their populations. The drive-time and radius tables measure the population around the county's main population center.