Primary Metal Manufacturing in Illinois
NAICS 331 · IL
This register lists 550 facilities in Illinois. The Bureau of Labor Statistics counted 336 establishments in the Primary Metal Manufacturing industry in Illinois in 2025. Mapleton Foundry in Mapleton employed 1,186 people in 2025.
SUMMARIZED FROM THE FEDERAL FIGURES ON THIS PAGE
Map, cities and product lines
Plants in Illinois16 FACILITIES
Listing 16 of 25: the facilities with a website, a size band or two sources on record. The rest are in site search.
| Facility | City | Employees | Status |
|---|---|---|---|
| Winnebago Foundry INC | South Beloit | 20–99 | ACTIVE |
| Top Die Casting CO | South Beloit | 100–499 | LIKELY ACTIVE |
| Rockford Foundries | Rockford | 1–19 | LIKELY ACTIVE |
| State Line Foundries INC | Roscoe | 100–499 | LIKELY ACTIVE |
| Gunite Corporation | Rockford | — | LIKELY ACTIVE |
| Arntzen CORP | Rockford | — | LIKELY ACTIVE |
| American Aluminum Extrusion HQ (Roscoe IL) | Roscoe | 100–499 | LIKELY ACTIVE |
| Behr Iron & Metal | Rockford | — | LIKELY ACTIVE |
| Stateline Foundries Inc | Roscoe | 20–99 | LIKELY ACTIVE |
| A-1 Wire Tech INC. | Rockford | — | UNVERIFIED |
| Always Aluminum | Rockford | — | UNVERIFIED |
| Essex Wire - Rockford | Rockford | — | UNVERIFIED |
| Neblock INC | Rockford | — | UNVERIFIED |
| Olson Aluminum Castings | Rockford | — | UNVERIFIED |
| Primecast, Inc.(former) | South Beloit | — | UNVERIFIED |
| Cincinnati Tool Steel Company | Rockford | 100–499 | LIKELY ACTIVE |
All primary metal manufacturing nationwide · All manufacturing in Illinois