| Wallón Holding AB | Kungsör | 0 tkr |
| Walrus Game Studios AB | Surahammar | 0 tkr |
| Wanda Sikorska AB | Västerås | 0 tkr |
| Wane Invest AB | Västerås | 0 tkr |
| Wannberg Konsult AB | Västerås | 0 tkr |
| Wässans AB | Västerås | 0 tkr |
| Wawab Holding AB | Västerås | 0 tkr |
| Waxin Fastigheter Aktiebolag | Arboga | 0 tkr |
| Way To Go AB | Västerås | 0 tkr |
| WB Equity AB | Västerås | 0 tkr |
| WBM Holding AB | Arboga | 0 tkr |
| WeBe & BSGA Fastigheter AB | Västerås | 0 tkr |
| WeBe & BSGA Holding AB | Västerås | 0 tkr |
| Wedab Holding AB | Västerås | 0 tkr |
| Welanders Fritidsgrejer AB | Surahammar | 0 tkr |
| Welora AB | Västerås | 0 tkr |
| Wenche Sörvåg AB | Västerås | 0 tkr |
| Wendelstam Invest AB | Västerås | 0 tkr |
| Wenniz AB | Västerås | 0 tkr |
| West-Ave Sweden AB | Västerås | 0 tkr |
| Westerås WorkWear AB | Västerås | 0 tkr |
| Westeros Entertainment AB | Västerås | 0 tkr |
| West-In Västerås AB | Västerås | 0 tkr |
| Westlake Balans AB | Västerås | 0 tkr |
| West Meadow Holding AB | Västerås | 0 tkr |
| Westra Aros Business Partner AB | Västerås | 0 tkr |
| Westra Aros Service AB | Västerås | 0 tkr |
| Westridge Power AB | Västerås | 0 tkr |
| Whitesurf Management AB | Västerås | 0 tkr |
| WIBI AB | Köping | 0 tkr |
| WideG AB | Skultuna | 0 tkr |
| Widens Holding AB | Arboga | 0 tkr |
| Widerström Holding AB | Västerås | 0 tkr |
| Widforss Industries AB | Västerås | 0 tkr |
| Widlunds i Västerås AB | Västerås | 0 tkr |
| Wikhult Holding AB | Västerås | 0 tkr |
| Wiklund Revision AB | Sala | 0 tkr |
| Wiljebrand Fastighetsmäklare AB | Strömsholm | 0 tkr |
| Williamvibergrickard Invest AB | Arboga | 0 tkr |
| Wilson Fastigheter AB | Västerås | 0 tkr |
| Wilson Invest AB | Västerås | 0 tkr |
| WinCo AB | Västerås | 0 tkr |
| Windcon AB | Västerås | 0 tkr |
| Windeed AB | Västerås | 0 tkr |
| Wingård Systems AB | Västerås | 0 tkr |
| Winther i Nannberga AB | Arboga | 0 tkr |
| WIWEB Consulting Holding AB | Västerås | 0 tkr |
| W.J. Bemanning & Logistik AB | Västerås | 0 tkr |
| WLA Fastighets AB | Köping | 0 tkr |
| WLS Holding AB | Västerås | 0 tkr |