| Navn | Postnummer | By |
|---|---|---|
| MAKEEN Gas Equipment Denmark A/S | 8940 | Randers SV |
| Mariendal El-Teknik A/S | 9000 | Aalborg |
| Maskinfabrikken Rational Aps | 2610 | Rødovre |
| Maskinsikkerhed ApS | 3500 | Værløse |
| Max Weishaupt A/S | 2600 | Glostrup |
| Megatrade | 2650 | Hvidovre |
| Micro Technic A-S | 5560 | Aarup |
| MillPart A/S | 6900 | Skjern |
| Mink-Bürsten ApS | 5492 | Vissenbjerg |
| Mirit Glas A/S | 2730 | Herlev |
| Momentum Energy Group A/S | 4000 | Roskilde |
| MTS Randers A/S | 8940 | Randers SV |
| Mul10 Metal A/S | 7130 | Juelsminde |
| Mul10 Prosafe A/S | 7130 | Juelsminde |
| Multi Køl & Energi A/S | 8220 | Brabrand |
| Munters A/S | 3520 | Farum |