St. Mary Parish, LA ZIP codes
There are 9 ZIP codes in St. Mary Parish, LA, in 9 towns, from 70340 to 70540. The largest are 70538 (Franklin), 70392 (Patterson) and 70342 (Berwick). 1 more crosses into it from a neighbouring county: 70544.
The parish seat is Franklin.
- ZIP codes
- 9
- Partly in it
- 1 more
- Towns
- 9
- Parish seat
- Franklin
- County FIPS
22101- State
- Louisiana
- Population
- 47,828
- Median household income
- $52,576
- Land area
- 559 sq mi
- Metro area
- Morgan City
St. Mary Parish ZIP codes by town
Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.
ZIP codes partly in St. Mary Parish
This ZIP code lies mostly in a neighbouring county but covers a twentieth or more of St. Mary Parish.
- 70544 Jeanerette · mostly in Iberia Parish
Map of St. Mary Parish ZIP codes
The ZIP codes of St. Mary Parish, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.
St. Mary Parish in numbers
About 47,828 people live in St. Mary Parish, in 18,463 households, the 23rd most populous of Louisiana's 64 counties. The median household income is $52,576 a year, 13% below the Louisiana median of $60,756 (US: $80,734). The median owner-occupied home is valued at $138,900 (36% below the Louisiana median), and median gross rent is $848 a month. The median age is 39.7; 13.6% of adults 25 and over hold a bachelor's degree or higher (27.0% across Louisiana); the average commute takes 23 minutes.
| Population | 47,828 |
|---|---|
| Households | 18,463 |
| Median age | 39.7 |
| Median household income | $52,576 |
| Median home value | $138,900 |
| Median gross rent | $848 |
| Bachelor's degree or higher | 13.6% |
| Mean commute | 23.2 min |
| Population density | 86 / sq mi |
U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.
Largest towns in St. Mary Parish
| Town | ZIP codes | Population |
|---|---|---|
| Morgan City | 1 | 11,064 |
| Franklin | 1 | 6,461 |
| Patterson | 1 | 5,744 |
| Berwick | 1 | 4,607 |
| Baldwin | 1 | 1,962 |
| Amelia | 1 | 1,712 |
| Charenton | 1 | 1,440 |
| Centerville | 1 | 685 |
Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.
Neighbouring counties
Counties that share a ZIP code with St. Mary Parish.
Not sure you are in St. Mary Parish? What county am I in? answers from your location, near a county line included.
Every ZIP code in St. Mary Parish, with figures
| ZIP | City | Type | Population | Median income | Median home |
|---|---|---|---|---|---|
70340 | Amelia , LA | Standard | 0 | — | — |
70342 | Berwick , LA | Standard | 4,607 | $51,580 | $212,400 |
70381 | Morgan City , LA | No street area | — | — | — |
70392 | Patterson , LA | Standard | 8,173 | $57,959 | $159,100 |
70514 | Baldwin , LA | Standard | 1,914 | $31,817 | $115,600 |
70522 | Centerville , LA | Standard | 495 | $26,321 | — |
70523 | Charenton , LA | Standard | 476 | $63,408 | $120,300 |
70538 | Franklin , LA | Standard | 12,464 | $52,407 | $117,800 |
70540 | Garden City , LA | No street area | — | — | — |
Cite this page
zipcodes.pro. “St. Mary Parish ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/la/county/st-mary
Underlying data is public domain or openly licensed — sources, vintages and licences.