| Name | Region |
|---|---|
| Bamboo Apps | Harju |
| Bank24 | Harju |
| Barking | Harju |
| Bauhub | Harju |
| BDC Consulting | Harju |
| Beamline OÜ | |
| Beast | |
| Beehosting | |
| BeeServer OÜ | Harju |
| BestIT OÜ | Harju |
| Bigbank | Harju |
| Bigbank AS | |
| Binalyze | |
| BiotaTec | |
| Bisly | |
| Biteful | |
| Bitlevex | |
| Bitskout OÜ | |
| Black Wing Foundation | Harju |
| Blakitech OÜ | Harju |
| Blockfrost.io | |
| BlocktradeOperations OÜ | |
| BluCloud Group OÜ | Harju |
| BluCloud Group OÜ | |
| BlueInk OÜ | |
| Bluemoon Interactive | Harju |
| Bolt Technology OÜ | Harju |
| Bondora Capital OÜ | |
| Botgate AI Technology OÜ | |
| BotGuard OÜ | Harju |
| BotSpace Technologies OÜ | |
| BPW Consulting | Harju |
| Brandner PCB OÜ | |
| Brka OÜ | |
| Brocoders | |
| Budgetto OÜ | |
| BugBox Ltd | |
| Bugvin Web Development OÜ | Harju |
| Build.works | |
| ByteAnt | |
| C3PA Network | |
| Cachet | Harju |
| CAD-süsteemide OÜ | Harju |
| CADi Eesti OÜ | Harju |
| Calidity | |
| Caotica | Harju |
| CareMate OÜ | |
| Catapult Labs OÜ | Harju |
| CATz Soft OÜ | Harju |
| Cellin Technologies |