| Apex Techno Ltd | |
| Apexure | |
| Apexweb | Dorset |
| APEXX Fintech Ltd | Greater London |
| APH Computers Ltd | |
| Apian Ltd | |
| APIS Assay Technologies Ltd | |
| Apis Partners, LLP | |
| APL Communications Ltd | Buckinghamshire |
| APM International | |
| Apnasoft Ltd | Leicestershire |
| Apogee Corporation Ltd | Kent |
| Apogee Data Consulting | Kent |
| Apogee Solutions Ltd | Hampshire |
| Apolitical Group Ltd | |
| Apollo I.T. Ltd | Devon |
| Apollo Informal Investment Ltd | |
| Apollo Internet Media | Hampshire |
| Apollo Scientific Ltd | |
| Apollo Therapeutics | |
| App Haus Ltd | |
| App4Grabs Ltd | |
| Apparel Systems | Berkshire |
| AppCan Ltd | |
| Appcelerate | |
| AppCentric | |
| Appeal Digital | |
| Appear Here | |
| Apperio Ltd | |
| Apperta Foundation | |
| AppFutures Ltd | |
| AppGameKit | |
| APPII | |
| AppInstitute | Nottinghamshire |
| Appitek Ltd | |
| Appius International Ltd | Dorset |
| Appiy Birmingham Ltd | West Midlands |
| Applaud Solutions UK Ltd | |
| Applause IT | |
| Apple Bentall Centre | Greater London |
| Apple Birmingham | West Midlands |
| Apple Bluewater | Kent |
| Apple Braehead | Glasgow |
| Apple Brent Cross | Greater London |
| Apple Bristol | Bristol |
| Apple Cardiff | Cardiff |
| Apple Chapelfield | Norfolk |
| Apple Churchill Square | East Sussex |
| Apple Covent Garden | Greater London |
| Apple Cribbs Causeway | Bristol |