| SERIO COMPANY LIMITED | | Live |
| Serio Asia Investment Limited | Private company limited by shares | Live |
| SERIO SALES LIMITED | Private company limited by shares | Dissolved |
| SERIONA GROUP LIMITED | Private company limited by shares | Live Commenced dormancy on 21-Jun-2016 |
| SERIOUS EXHIBITION CONSULTANT CO., LIMITED | Private company limited by shares | Dissolved |
| SERIOUS MARKETING COMMUNICATIONS (HK) LIMITED | Private company limited by shares | Live |
| Serious Enterprise Management Consulting (HK) Limited | Private company limited by shares | Live |
| Serious Employment Centre Limited | Private company limited by shares | Live |
| SERIOUS LANDSCAPING & ENGINEERING LIMITED | Private company limited by shares | Live |
| SERIOUS ENTERTAINMENT LIMITED | | Live |
| SERIOUS FASHION CO., LIMITED | Private company limited by shares | Live |
| SERIOUS FISH LIMITED | Private company limited by shares | Live |
| SERIOUS GROUP COMPANY LIMITED | Private company limited by shares | Live |
| SERIOUS INTERNATIONAL LIMITED | Private company limited by shares | Live |
| SERIOUS MARKETING LIMITED | Private company limited by shares | Live |
| SERIOUS MODE LIMITED | | Live |
| Serious Monkey Limited | Private company limited by shares | Live |
| Y Show Serious Limited | Private company limited by shares | Live |
| SERIOUS SPACE LIMITED | Private company limited by shares | Live |
| SERIOUS STAGING LIMITED | Private company limited by shares | Live |
| Serious Tech Limited | Private company limited by shares | Live |
| FRICK SERIOUS ELECTRONIC TECHNOLOGY (H.K.) CO. LIMITED | Private company limited by shares | Dissolved |
| Serious Learning Tool Limited | Private company limited by shares | Live |
| Why So Serious Training Limited | Private company limited by shares | Live |
| Serious Tubes Limited | Private company limited by shares | Live |
| WINE SO SERIOUS LIMITED | Private company limited by shares | Live |
| SERIOUSLEE 41 LIMITED | | Live |
| SERIOUSLEE 42 LIMITED | | Live |
| SERIOUSLEE 43 LIMITED | | Live |
| SERIOUSLEE 44 LIMITED | | Live |
| SERIOUSLEE 45 LIMITED | | Live |
| SERIOUSLY ROMANTIC HK LIMITED | Private company limited by shares | Live |