| Navn | Postnummer | By |
|---|---|---|
| Jakob Albertsen A/S | 5700 | Svendborg |
| Jens S Transmissioner A/S | 2630 | Taastrup |
| JEROS A/S | 5750 | Ringe |
| JIMCO A/S | 5900 | Rudkøbing |
| JLM teknik ApS | 9500 | Hobro |
| Job i Fokus | 2200 | København N |
| John Crane Danmark | 3650 | Ølstykke |
| Johnson Metal A/S | 2630 | Tåstrup |
| JOM Food & Kitchen Machinery A/S | 7700 | Thisted |
| jpbc A/S | 8840 | Rødkærsbro |
| Justsen Energiteknik A/S | 8220 | Brabrand |
| JW Industri A/S | 7430 | Ikast |