| A-List Hair Academy Ltd | Education | 2022 |
| A-Z Community Consulting Ltd | Professional & scientific | 2023 |
| A-Z Motors (Peterborough) Limited | Wholesale & retail | 2018 |
| A. & P. H. Development Company Ltd. | Real estate | 1988 |
| A. E. Tebbs (Farms) Limited | Real estate | 1960 |
| A. Mika Limited | Information & communication | 2017 |
| A. Z. Technical Limited | Health & social care | 1999 |
| A.B.C. (Stainless) Limited | Manufacturing | 1980 |
| A.B.C. Bearings Limited | Extraterritorial | 1987 |
| A.B.C. Stainless (Holdings) Limited | Financial services | 2008 |
| A.B.G. Farms Limited | Agriculture & fishing | 2013 |
| A.D. Madureira Peterborough Ltd | Administrative & support | 2024 |
| A.D.M. Peterborough Ltd | Administrative & support | 2025 |
| A.F. Smith and SON (Group) Limited | Financial services | 1952 |
| A.G.A Brickwork Limited | Construction | 2023 |
| A.G.E. Electrical Services Limited | Construction | 1989 |
| A.Glenn & Sons,Limited | | 1926 |
| A.J. Power (GB) Limited | Manufacturing | 2022 |
| A.J.M. Residential Developments Limited | Construction | 2016 |
| A.L Driving Services Ltd | Transport & logistics | 2024 |
| A.M. Herman Ltd | Construction | 2024 |
| A.N. DAR Properties Limited | Construction | 2003 |
| A.P Patrick Construction Ltd | Construction | 2022 |
| A.P Patrick Group Ltd | Administrative & support | 2024 |
| A.P.H Carpentry Ltd | Manufacturing | 2025 |
| A.P.H. (Engineering) Limited | Professional & scientific | 1987 |
| A.P.H. (Hire) Limited | Professional & scientific | 1987 |
| A.P.H. Farm Services Limited | Professional & scientific | 1991 |
| A.P.Railway Trainer Limited | Transport & logistics | 2025 |
| A.R Studholme Maintenance Ltd | Extraterritorial | 2024 |
| A.R.C. Welding Limited | Construction | 2003 |
| A.S Mortgage Solutions Ltd | Financial services | 2024 |
| A.S. Properties (Peterborough) Limited | Construction | 2016 |
| A.Service&Co Ltd | Transport & logistics | 2024 |
| A.T.S Air Testing Solutions and Labouring Ltd | Construction | 2019 |
| A.Tariq Ltd | Health & social care | 2015 |
| A.W.L. Construction Limited | Construction | 2010 |
| A1 Campers Ltd | Wholesale & retail | 2016 |
| A1 Fencing Limited | Construction | 2002 |
| A1 Fresh Foods PB Ltd | Hospitality | 2021 |
| A1 Logistics Peterborough Ltd | Transport & logistics | 2025 |
| A1 Minicabs Peterborough Ltd | Transport & logistics | 2025 |
| A1 Motorhome Hire Ltd | Administrative & support | 2014 |
| A1 Sameday Couriers Limited | Transport & logistics | 2020 |
| A1 Stadium Diner Limited | Hospitality | 2024 |
| A1 Steel Limited | Manufacturing | 1988 |
| A1 Truck Stop Colsterworth Limited | Transport & logistics | 2017 |
| A1 Tyres and Auto Repair Ltd | Wholesale & retail | 2023 |
| A10 Motors Ltd | Professional & scientific | 2015 |
| A15 Cars Ltd. | Wholesale & retail | 2019 |
| A16 Autos Ltd | Wholesale & retail | 2025 |
| A2COM UK Ltd | Information & communication | 2019 |
| A2Z Taxi Ltd | Transport & logistics | 2024 |
| A3RGK Property Limited | Real estate | 2025 |
| AA & SA Investments Ltd | Real estate | 2025 |
| AA Accountants Ltd | Professional & scientific | 2007 |
| AA Analytics Ltd | Information & communication | 2025 |
| AA Brickwork Limited | Construction | 2014 |
| AA Car Wash Limited | Administrative & support | 2025 |
| AA Carpenter Ltd | Manufacturing | 2018 |
| AA Claims Ltd | Professional & scientific | 2004 |
| AA Daily Fresh Limited | Wholesale & retail | 2023 |
| AA GAS Services Peterborough Limited | Construction | 2025 |
| AA Logistic Solution Ltd | Transport & logistics | 2021 |
| AA Motoring Group Ltd | Wholesale & retail | 2023 |
| AA Peterborough Letting Limited | Households | 2021 |
| AA Property Holding Limited | Real estate | 2016 |
| AA Trade Motors Ltd | Wholesale & retail | 2026 |
| AA Vital Healthcare Ltd | Health & social care | 2026 |
| AA Whittlesey Computers Ltd | Information & communication | 2015 |
| AAA & KR Ltd | Hospitality | 2020 |
| AAA Engineering Services Limited | Professional & scientific | 2024 |
| AAA Supreme Ltd | Wholesale & retail | 2023 |
| Aaarabisk Ltd | Transport & logistics | 2021 |
| AAB Trans Limited | Transport & logistics | 2015 |
| Aacloud Solutions Limited | Information & communication | 2023 |
| Aacp Ltd | Other services | 2019 |
| Aadhi Zion Ltd | Wholesale & retail | 2026 |
| AAH Property Renovations Ltd | Real estate | 2025 |
| Aairah's Desserts Ltd | Hospitality | 2025 |
| AAM Drivers Ltd | Administrative & support | 2025 |
| AAM Transport Driver Ltd | Transport & logistics | 2021 |
| Aamali Ltd | Other services | 2024 |
| Aams VH Ltd | Health & social care | 2021 |
| Aanisa Limited | Transport & logistics | 2025 |
| Aaran Advisory Ltd | Real estate | 2023 |
| Aaran Real Estates Ltd | Real estate | 2025 |
| Aarchar Consulting Ltd | Information & communication | 2019 |
| Aarchar Summits Ltd | Real estate | 2025 |
| Aarga Care Ltd | Health & social care | 2022 |
| Aaron Group Ltd | Construction | 2018 |
| Aaronas Ltd | Wholesale & retail | 2021 |
| AAS Transport Ltd | Transport & logistics | 2025 |
| Aashni&Asvin Ltd | Wholesale & retail | 2022 |
| Aasp Group Limited | Wholesale & retail | 2021 |
| Aasp Holdings Ltd | Transport & logistics | 2020 |
| Aastha Properties Ltd | Real estate | 2025 |
| AB & CB Holdings Limited | Administrative & support | 2020 |
| AB Autoparts Ltd | Water & waste | 2020 |
| AB Bodyworks Ltd | Wholesale & retail | 2020 |