| Tohny Tjernkvist AB | Västerås | 0 tkr |
| Tolves Konsult AB | Arboga | 0 tkr |
| Tolv Projekt Holding AB | Västerås | 0 tkr |
| Tomasbo lantbruk AB | Västerfärnebo | 0 tkr |
| Tomas Johansson Holding AB | Västerås | 0 tkr |
| Tomberg Holding AB | Hallstahammar | 0 tkr |
| Tom Charles AB | Fagersta | 0 tkr |
| Tommy Bennström AB | Falun | 0 tkr |
| Tommy Nilsson Elkraft & Digitalisering AB | Sala | 0 tkr |
| Tomuch Västerås AB | Västerås | 0 tkr |
| Torbjörn Ericson Engineering AB | Skultuna | 0 tkr |
| Torbjörn Hedevärn Holding AB | Västerås | 0 tkr |
| Tornkransen Fastigheter AB | Västerås | 0 tkr |
| T Orpana:s Bygg o anläggning konsult AB | Surahammar | 0 tkr |
| Torperiet Invest AB | Sala | 0 tkr |
| TORRO HOLDING AB | Sala | 0 tkr |
| Totalbyggen i Västerås Holding AB | Västerås | 0 tkr |
| Toteel Transport AB | Angered | 0 tkr |
| TOTI Holding AB | Västerås | 0 tkr |
| TP Teknopartner AB | Västerås | 0 tkr |
| Trackteam Holding AB | Falun | 0 tkr |
| Tracon Group AB | Västerås | 0 tkr |
| Tradeidé AB | Hallstahammar | 0 tkr |
| Transporttjänst i Västerås AB | Ransta | 0 tkr |
| Transtronic Holding AB | Köping | 0 tkr |
| Trax Scandinavia AB | Västerås | 0 tkr |
| Tre 12 AB | Fagersta | 0 tkr |
| Tremella AB | Vällingby | 0 tkr |
| Tre Streck Group AB | Västerås | 0 tkr |
| Trienta AB | Norberg | 0 tkr |
| Trissentum Invest AB | Västerås | 0 tkr |
| Trollske Holding AB | Kungsör | 0 tkr |
| Trumvallen Invest Aktiebolag | Västerås | 0 tkr |
| TRY Dental AB | Västerås | 0 tkr |
| TS Montage AB | Västerås | 0 tkr |
| TTB i Västerås AB | Västerås | 0 tkr |
| TTCzarnecki Konsult AB | Norberg | 0 tkr |
| TTSJ Invest AB | Skultuna | 0 tkr |
| Tunby Blästring & Målning Holding AB | Västerås | 0 tkr |
| Tunby Holding AB | Västerås | 0 tkr |
| Tunbytorp Bygg Västerås AB | Västerås | 0 tkr |
| Tunbytorp Finsnickeri AB | Västerås | 0 tkr |
| Tunbytorp Transport AB | Västerås | 0 tkr |
| Tu Ph Holding AB | Västerås | 0 tkr |
| Tuppa AB | Västerås | 0 tkr |
| Turbovägen Holding AB | Surahammar | 0 tkr |
| Twindej Holding AB | Västerås | 0 tkr |
| Twistboxesholding AB | Västerås | 0 tkr |
| Twistboxes Pro AB | Västerås | 0 tkr |
| TXK Estate AB | Kungsör | 0 tkr |