Assumption Parish, LA ZIP codes
There are 7 ZIP codes in Assumption Parish, LA, in 7 towns, from 70339 to 70393. The largest are 70380 (Morgan City), 70390 (Napoleonville) and 70339 (Pierre Part).
The parish seat is Napoleonville.
- ZIP codes
- 7
- Towns
- 7
- Parish seat
- Napoleonville
- County FIPS
22007- State
- Louisiana
- Population
- 20,484
- Median household income
- $51,423
- Land area
- 344 sq mi
- Area code
- 985
- Metro area
- Baton Rouge
Assumption Parish ZIP codes by town
- Napoleonville (parish seat)
- 70390
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.
Map of Assumption Parish ZIP codes
The ZIP codes of Assumption 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.
Assumption Parish in numbers
About 20,484 people live in Assumption Parish, in 8,830 households, the 43rd most populous of Louisiana's 64 counties. The median household income is $51,423 a year, 15% below the Louisiana median of $60,756 (US: $80,734). The median owner-occupied home is valued at $150,300 (31% below the Louisiana median), and median gross rent is $810 a month. The median age is 42.8; 13.8% of adults 25 and over hold a bachelor's degree or higher (27.0% across Louisiana); the average commute takes 29 minutes.
| Population | 20,484 |
|---|---|
| Households | 8,830 |
| Median age | 42.8 |
| Median household income | $51,423 |
| Median home value | $150,300 |
| Median gross rent | $810 |
| Bachelor's degree or higher | 13.8% |
| Mean commute | 29.2 min |
| Population density | 60 / 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 Assumption Parish
| Town | ZIP codes | Population |
|---|---|---|
| Morgan City | 1 | 11,064 |
| Pierre Part | 1 | 2,308 |
| Labadieville | 1 | 1,408 |
| Belle Rose | 1 | 1,400 |
| Paincourtville | 1 | 1,008 |
| Napoleonville | 1 | 511 |
| Plattenville | 1 | 117 |
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 Assumption Parish.
- Ascension Parish (11)
- Terrebonne Parish (12)
- Lafourche Parish (13)
- St. Martin Parish (4)
- St. Mary Parish (9)
Not sure you are in Assumption Parish? What county am I in? answers from your location, near a county line included.
Every ZIP code in Assumption Parish, with figures
| ZIP | City | Type | Population | Median income | Median home |
|---|---|---|---|---|---|
70339 | Pierre Part , LA | Standard | 4,848 | $51,659 | $170,500 |
70341 | Belle Rose , LA | Standard | 3,690 | $35,346 | $88,500 |
70372 | Labadieville , LA | Standard | 1,968 | $40,659 | $105,200 |
70380 | Morgan City , LA | Standard | 20,529 | $54,595 | $141,600 |
70390 | Napoleonville , LA | Standard | 7,160 | $58,667 | $162,900 |
70391 | Paincourtville , LA | Standard | 0 | — | — |
70393 | Plattenville , LA | Standard | 117 | $19,256 | $214,900 |
Cite this page
zipcodes.pro. “Assumption Parish ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/la/county/assumption
Underlying data is public domain or openly licensed — sources, vintages and licences.