| Bardo | Barcelona |
| Barnaciber | Barcelona |
| Barnahosting | Barcelona |
| BarnaWeb | Barcelona |
| Basesoft | A Coruña |
| Basque Center for Applied Mathematics | Biscay |
| Basque Center on Cognition, Brain and Language | |
| BAU, Centro Universitario de Diseño de Barcelona | Barcelona |
| BCN informatica | Barcelona |
| BCN Peptides, S.A.U. | Barcelona |
| BCN3D Technologies, Inc. | |
| Bcnserveis.com | Barcelona |
| BCNWEBTEAM | Barcelona |
| BCOM | Barcelona |
| Bcombinator | Barcelona |
| BCome | Barcelona |
| Bdeo | Madrid |
| Beabloo | Barcelona |
| Beato Digital | Alicante |
| BeBanjo | Madrid |
| BeCytes Biotechnologies | Barcelona |
| Bedrock Intelligence, S.L.U. | Asturias |
| Bee the Data, S.L. | Barcelona |
| Beedata Analytics, S.L. | Barcelona |
| BeeDIGITAL AI, S.A.U. | Madrid |
| Beemeral, S.L. | Málaga |
| Begoñako Andra Mari Irakasleen Unibertsitate Eskola | |
| Beleader Internet Marketing, S.L. | Madrid |
| Belsati Sistemas | Barcelona |
| Belvo | Barcelona |
| Bemobile | Barcelona |
| Benotac | Madrid |
| BEONx | Salamanca |
| Berba Translations, S.L. | Biscay |
| BeRepublic Networks, S.L. | Barcelona |
| Berkano Systems | Madrid |
| Berrly | Barcelona |
| Best Marketing | Madrid |
| Best Search Consultores, S.L. | Madrid |
| BETA Mayorista Informático, S. L. | Zaragoza |
| Betran.info | Barcelona |
| Betterplace | Asturias |
| beWanted | Madrid |
| BGS Software y Control Industrial, S.L. | Barcelona |
| Biboss | Barcelona |
| Bic Araba | Álava |
| Bic Gipuzkoa | Gipuzkoa |
| Biel Glasses, S.L. | Barcelona |
| Big Sur Ventures | Madrid |
| Bigbank AS en España | |