| Abbot Group Limited | | | bribery | 2012 | UK-COPFS | £5,600,000 |
| Abbott and Frost Estate Agents Limited | | | price-fixing or anti-competitive practices | 2017 | UK-CMA | £30,099 |
| Actavis UK Ltd. | Intas Pharmaceuticals Ltd. | pharmaceuticals | price-fixing or anti-competitive practices | 2016 | UK-CMA | £1,542,860 |
| Adret Ltd and Berangere Ltd | | | energy market violation | 2015 | UK-OFGEM | £0 |
| Advanced Payment Solutions | | | price-fixing or anti-competitive practices | 2022 | UK-PSR | £755,419 |
| Advanz Pharma | Nordic Capital | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2021 | UK-CMA | £40,900,000 |
| Ageas Insurance Ltd. | | | price-fixing or anti-competitive practices | 2011 | UK-OFT | £0 |
| Airbus SE | Airbus | aerospace and military contracting | bribery | 2020 | UK-SFO | £991,000,000 |
| Airline Services Limited | | | bribery | 2020 | UK-SFO | £2,979,685 |
| Alissa Healthcare Research Ltd. | | | price-fixing or anti-competitive practices | 2020 | UK-CMA | £174,912 |
| Alliance Pharmaceuticals Limited and Alliance Pharma plc | Alliance Pharma PLC | pharmaceuticals | price-fixing or anti-competitive practices | 2022 | UK-CMA | £7,900,000 |
| allpay Limited | | | price-fixing or anti-competitive practices | 2022 | UK-PSR | £28,553 |
| Alphabet Inc. and Google UK Ltd. and Google LLC | Alphabet Inc. | information technology | price-fixing or anti-competitive practices | 2022 | UK-CMA | £0 |
| Alsford Page & Gems Limited | | | consumer protection violation | 2021 | UK-FCA | £399,902 |
| Alstom Network UK Ltd | Alstom | miscellaneous energy products and systems | bribery | 2019 | UK-SFO | £16,400,000 |
| Alstom Power Ltd | GE Vernova | industrial equipment | bribery | 2018 | UK-SFO | £18,038,000 |
| Amec Foster Wheeler Limited | Wood Group | oilfield services and supplies | bribery | 2021 | UK-SFO | £103,000,000 |
| Amilco Ltd. | | | price-fixing or anti-competitive practices | 2020 | UK-CMA | £0 |
| Ampoweruk | | | energy market violation | 2021 | UK-OFGEM | £3,590,237 |
| Annagram Estates Limited dba CJ Hole | | | price-fixing or anti-competitive practices | 2017 | UK-CMA | £0 |
| Area Sq Ltd. and Cube Interior Solutions Ltd. and Fourfront Group Ltd. and Fourfront Holdings Ltd. | | | price-fixing or anti-competitive practices | 2019 | UK-CMA | £4,143,304 |
| Aria Foods Limited and Arla Foods UK Limited | Arla Foods | food products | price-fixing or anti-competitive practices | 2011 | UK-OFT | £0 |
| Asda | EG Group | retailing | price-fixing or anti-competitive practices | 2023 | UK-CMA | £0 |
| Asda Group Ltd | EG Group | retailing | price-fixing or anti-competitive practices | 2023 | UK-CMA | £30,000 |
| Asda Stores Ltd. and Asda Group Ltd. and Wal-Mart Stores (UK) Ltd. and Broadstreet Great Wilson Europe Ltd. | EG Group | retailing | price-fixing or anti-competitive practices | 2011 | UK-OFT | £9,100,000 |
| Aspen Pharmacare Holdings Ltd. et al. | | | price-fixing or anti-competitive practices | 2020 | UK-CMA | £10,101,954 |
| Assist UK Group Limited | | | consumer protection violation | 2021 | UK-FCA | £0 |
| Associated Lead Mills Limited and Royston Sheet Lead Limited and International Metal Industries Limited | | | price-fixing or anti-competitive practices | 2020 | UK-CMA | £1,510,228 |
| ATG Media | | | price-fixing or anti-competitive practices | 2017 | UK-CMA | £0 |
| Auden Mckenzie (Pharma Division) Ltd. and Accord-UK Ltd. | Intas Pharmaceuticals Ltd. | pharmaceuticals | price-fixing or anti-competitive practices | 2020 | UK-CMA | £2,882,238 |
| Auden Mckenzie and Actavis UK | Intas Pharmaceuticals Ltd. | pharmaceuticals | price-fixing or anti-competitive practices | 2023 | UK-CMA | £130,000,000 |
| Avanti Gas Limited | UGI Corp. | utilities and power generation | price-fixing or anti-competitive practices | 2012 | UK-OFT | £0 |
| Aviva Insurance UK Ltd. | Aviva PLC | financial services | price-fixing or anti-competitive practices | 2011 | UK-OFT | £0 |
| Avro Energy | | | energy market violation | 2021 | UK-OFGEM | £30,000 |
| AXA Insurance UK plc | AXA | financial services | price-fixing or anti-competitive practices | 2011 | UK-OFT | £0 |
| B Limited | | | bribery | 2016 | UK-COPFS | £2,200,000 |
| BAE Systems plc | BAE Systems | aerospace and military contracting | bribery | 2010 | UK-SFO | £30,000,000 |
| Balmoral Tanks Ltd. and Balmoral Group Holdings Ltd. | | | price-fixing or anti-competitive practices | 2019 | UK-CMA | £130,000 |
| Bank of Ireland UK plc | Bank of Ireland | financial services | banking violation | 2021 | UK-CMA | £0 |
| Barclays Bank plc | Barclays | financial services | foreign exchange market manipulation | 2015 | UK-FCA | £284,432,000 |
| Barclays Bank plc | Barclays | financial services | interest rate benchmark manipulation | 2012 | UK-FSA | £59,500,000 |
| Barclays Bank plc | Barclays | financial services | price-fixing or anti-competitive practices | 2011 | UK-OFT | £0 |
| Berendsen Cleanroom Services Ltd. fka Micronclean (Newbury) Ltd. and Berendsen plc | | | price-fixing or anti-competitive practices | 2017 | UK-CMA | £1,197,956 |
| Better Mobility Limited | | | price-fixing or anti-competitive practices | 2014 | UK-OFT | £0 |
| BHK (UK) Ltd. and BHK Holz-u Kunststoff KG | | | price-fixing or anti-competitive practices | 2017 | UK-CMA | £0 |
| Bluu Solutions Ltd and Bluuco Ltd. and Tetris Projects Ltd. and Jones Lang LaSalle Inc. | | | price-fixing or anti-competitive practices | 2019 | UK-CMA | £0 |
| BP Oil UK Limited | BP | oil and gas | price-fixing or anti-competitive practices | 2012 | UK-OFT | £0 |
| Brand-Rex Ltd | | | bribery | 2015 | UK-COPFS | £212,800 |
| Bristol Water | Pennon Group PLC | utilities and power generation | price-fixing or anti-competitive practices | 2015 | UK-OFWAT | £0 |
| British Airways | International Airlines Group | airlines | price-fixing or anti-competitive practices | 2012 | UK-OFT | £58,500,000 |
| British Gas | Centrica | utilities and power generation | energy market violation | 2023 | UK-OFGEM | £3,370,000 |
| British Gas | Centrica | utilities and power generation | consumer protection violation | 2020 | UK-OFGEM | £1,728,070 |
| British Gas | Centrica | utilities and power generation | energy market violation | 2015 | UK-OFGEM | £10,600,000 |
| British Gas | Centrica | utilities and power generation | energy market violation | 2015 | UK-OFGEM | £500,000 |
| British Gas Trading Limited | Centrica | utilities and power generation | price-fixing or anti-competitive practices | 2016 | UK-CMA | £0 |
| British Gas Trading Limited | Centrica | utilities and power generation | energy market violation | 2017 | UK-OFGEM | £4,500,000 |
| British Gas Trading Limited | Centrica | utilities and power generation | energy market violation | 2011 | UK-OFGEM | £1,000,000 |
| British Gas/ Centrica | Centrica | utilities and power generation | consumer protection violation | 2021 | UK-OFGEM | £1,660,272 |
| British Telecommunications plc | BT | telecommunications | price-fixing or anti-competitive practices | 2017 | UK-OFCOM | £300,000 |
| British Telecommunications plc | BT | telecommunications | price-fixing or anti-competitive practices | 2017 | UK-OFCOM | £42,000,000 |
| British Telecommunications plc | BT | telecommunications | consumer protection violation | 2014 | UK-OFCOM | £1,200,000 |
| British Telecommunications plc | BT | telecommunications | price-fixing or anti-competitive practices | 2013 | UK-OFCOM | £2,896,800 |
| British Telecommunications plc | BT | telecommunications | price-fixing or anti-competitive practices | 2012 | UK-OFCOM | £117,042,000 |
| Brown and Mason Group Ltd | | | price-fixing or anti-competitive practices | 2023 | UK-CMA | £2,400,000 |
| BT Group plc | BT | telecommunications | price-fixing or anti-competitive practices | 2020 | UK-OFCOM | £6,300,000 |
| Bulb | | | energy market violation | 2023 | UK-OFGEM | £1,830,000 |
| Bulb | | | consumer protection violation | 2020 | UK-OFGEM | £1,757,837 |
| Cadent Gas Limited | Cadent Gas Limited | utilities and power generation | energy market violation | 2019 | UK-OFGEM | £44,000,000 |
| Calor Gas Limited | SHV Holdings | diversified | price-fixing or anti-competitive practices | 2012 | UK-OFT | £0 |
| Calor Gas Northern Ireland | SHV Holdings | diversified | price-fixing or anti-competitive practices | 2012 | UK-OFT | £0 |
| Cantillon Ltd and Cantillon Holdings Ltd | | | price-fixing or anti-competitive practices | 2023 | UK-CMA | £1,920,000 |
| Careco (UK) Limited | | | price-fixing or anti-competitive practices | 2013 | UK-OFT | £0 |
| Careco (UK) Ltd. | | | price-fixing or anti-competitive practices | 2014 | UK-OFT | £0 |
| Casio Electronics Co. Ltd. and Casio Computer Co., Ltd. | Casio Computer Co. | miscellaneous manufacturing | price-fixing or anti-competitive practices | 2019 | UK-CMA | £3,695,535 |
| Castles Property Services Limited | | | price-fixing or anti-competitive practices | 2015 | UK-CMA | £17,348 |
| Celesio AG and Lloyds Pharmacy Limited | | | price-fixing or anti-competitive practices | 2014 | UK-OFT | £0 |
| Central Networks East plc and Central Networks West plc | | | energy market violation | 2011 | UK-OFGEM | £400,000 |
| Certas Energy UK Limited and DCC plc | DCC PLC | business services | price-fixing or anti-competitive practices | 2014 | UK-CMA | £0 |
| Ciceley Commercials Limited and Ciceley Limited | | | price-fixing or anti-competitive practices | 2013 | UK-OFT | £659,675 |
| Cinven | Cinven Group | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2021 | UK-CMA | £37,100,000 |
| Cinven Capital Management (V) GP Ltd. and Cinven Partners LLP et al. | Cinven Group | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2022 | UK-CMA | £4,856,620 |
| Cirrus and Careline UK Monitoring Limited and Peverel Building Technologies Limited | | | price-fixing or anti-competitive practices | 2013 | UK-OFT | £0 |
| Citibank N.A. | Citigroup | financial services | foreign exchange market manipulation | 2014 | UK-FCA | £225,575,000 |
| Citigroup Global Markets Limited | Citigroup | financial services | price-fixing or anti-competitive practices | 2023 | UK-CMA | £0 |
| Clear Channel UK | Clear Channel Outdoor Holdings | business services | price-fixing or anti-competitive practices | 2012 | UK-OFT | £0 |
| Clifford Devlin Ltd | | | price-fixing or anti-competitive practices | 2023 | UK-CMA | £423,615 |
| Co-operative Group Limited | Co-operative Group Limited | retailing | Groceries Supply Code of Conduct violation | 2019 | UK-GCA | £0 |
| Consultant Eye Surgeons Partnership (CESP) Ltd. | | | price-fixing or anti-competitive practices | 2015 | UK-CMA | £382,500 |
| Consumer Money Worries Ltd | | | consumer protection violation | 2021 | UK-FCA | £0 |
| Cooperatieve Centrale Raiffeisen-Boerenleenbank B.A. | Rabobank | financial services | interest rate benchmark manipulation | 2013 | UK-FCA | £105,000,000 |
| Copart, Inc. and CPRT LLP and Copart UK Ltd. | Copart Inc. | information services | price-fixing or anti-competitive practices | 2023 | UK-CMA | £2,500,000 |
| Copart, Inc.and CPRT LLP and Copart UK Limited | Copart Inc. | information services | price-fixing or anti-competitive practices | 2023 | UK-CMA | £25,000 |
| Coriolis Projects Ltd. | | | price-fixing or anti-competitive practices | 2019 | UK-CMA | £7,735 |
| CPL Distribution Limited and CPL Industries Holdings Limited | | | price-fixing or anti-competitive practices | 2018 | UK-CMA | £2,816,514 |
| CPM Group Limited | Marshalls PLC | building materials | price-fixing or anti-competitive practices | 2019 | UK-CMA | £4,000,000 |
| Crosfill & Archer Claims Limited | | | privacy violation | 2021 | UK-FCA | £110,000 |
| CST Industries (UK) Ltd. and CST Industries Inc. | | | price-fixing or anti-competitive practices | 2016 | UK-CMA | £0 |
| Dairy Crest Limited and Dairy Crest Group plc | Saputo | food products | price-fixing or anti-competitive practices | 2011 | UK-OFT | £7,140,000 |
| DCC Energy Limited | DCC PLC | business services | price-fixing or anti-competitive practices | 2012 | UK-OFT | £0 |
| Debt Help Limited | | | consumer protection violation | 2021 | UK-FCA | £0 |
| Delta Gas and Power Limited | | | energy market violation | 2023 | UK-OFGEM | £70,000 |
