| "Streonshalh" Whitby Limited | Households | 1982 |
| 11 Crescent Avenue (Whitby) Ltd | Households | 2018 |
| 11 Normanby Terrace Management Company Limited | Households | 2011 |
| 12 Bagdale Management Company Limited | Households | 2013 |
| 12 Esplanade Whitby Management Company Limited | Households | 2009 |
| 12 Langdale Terrace Management Company Limited | Households | 1991 |
| 12 Royal Crescent (Whitby) Limited | Households | 2001 |
| 14 Prospect Hill (Whitby) Limited | Households | 2006 |
| 15 and 15A Silver Street Management Company Limited | Real estate | 2013 |
| 15 Prospect Hill (Whitby) Limited | Households | 2019 |
| 17 Abbey Terrace Management Company Limited | Hospitality | 2012 |
| 17/18 Haggersgate (Whitby) Limited | Households | 2015 |
| 19 Hudson Street Management Company Limited | Households | 2018 |
| 1A Lansdowne Way RTM Company Limited | Households | 2014 |
| 20 Falcon Ltd | Households | 2024 |
| 24 Crescent Avenue Management (Whitby) Limited | Households | 2013 |
| 25 Crescent Avenue Management Company Limited | Other services | 2002 |
| 3-MINUTE Arts CIC | Arts & recreation | 2023 |
| 3WAYS Kitchens & Interiors Ltd | Manufacturing | 2021 |
| 5 Windsor Terrace (Whitby) Limited | Professional & scientific | 2006 |
| 7 Church Square (Whitby) Management Company Limited | Extraterritorial | 2014 |
| 7 Ladysmith Avenue (Whitby) Management Company Limited | Hospitality | 2007 |
| 8 Ladysmith Avenue (Whitby) Limited | Hospitality | 2008 |
| 9 Church Street (Whitby) Limited | Households | 2017 |
| A & D Cleaning Services Limited | Administrative & support | 2008 |
| A & F Lloyd Training Limited | Information & communication | 2022 |
| A & M Company Secretarial Services Ltd | Administrative & support | 2007 |
| A & S Construction & Groundwork Limited | Construction | 2005 |
| A B Property Management (Whitby) Limited | Real estate | 2004 |
| A CUT Above CNC Ltd | Agriculture & fishing | 2025 |
| A P Developments (Whitby) Limited | Construction | 2005 |
| A P Jackson (Butchers) Limited | Wholesale & retail | 2001 |
| A R Kitney Design Ltd | Professional & scientific | 2023 |
| A&D Wilkie Ltd | Transport & logistics | 2009 |
| A.C.J. Industrial Limited | Wholesale & retail | 1974 |
| A.L. Waring Properties Ltd | Construction | 2014 |
| A.S.Page Management Services Ltd | Administrative & support | 2008 |
| A1 Ice Creams Limited | Hospitality | 2023 |
| A1 Multi-Trade Ltd | Construction | 2019 |
| AB Agri Drones Ltd | Agriculture & fishing | 2025 |
| AB Trading (Yorkshire) Limited | Hospitality | 2020 |
| Abbey Cleaning Solutions Ltd | Administrative & support | 2021 |
| Abbey Farm Minerals Limited | Professional & scientific | 2013 |
| Abbey Farm Showfield Limited | Administrative & support | 2020 |
| Abbey GAS (Whitby) Limited | Construction | 2012 |
| Abbey Holiday Lets Limited | Hospitality | 2024 |
| Abbey Park Holidays Limited | Hospitality | 2023 |
| Abbey Taxis Whitby Ltd | Transport & logistics | 2023 |
| Abbey Terrace Management (Whitby) Limited | Households | 1990 |
| Accounting & Management Limited | Professional & scientific | 2007 |
| Action Solutions Gift Cards Limited | Administrative & support | 2006 |
| Active Learning Childcare Services CIC | Education | 2024 |
| AD Noble Ltd | Administrative & support | 2023 |
| Adam Stringer Joinery and Building Limited | Construction | 2015 |
| Adamski Bros. Groundcare Ltd | Construction | 2022 |
| Adamski Bros. Property Ltd | Real estate | 2026 |
| Adele Rose Ltd | Wholesale & retail | 2021 |
| Adept Investing Ltd | Financial services | 2015 |
| Adgl Limited | Mining & quarrying | 2013 |
| Adrian Glasser Consulting Ltd | Professional & scientific | 2021 |
| ADY 1 Limited | Mining & quarrying | 2011 |
| Aetherweb Limited | Information & communication | 1999 |
| Afterglow Tanning Studio Darlington Ltd | Other services | 2023 |
| Afterglow Tanning Studio Holdings Ltd | Financial services | 2023 |
| Afterglow Tanning Studio Lingfield Ltd | Other services | 2025 |
| Afterglow Tanning Studio Middlesbrough Ltd | Other services | 2026 |
| AGI DIY Ltd | Wholesale & retail | 2006 |
| Aguirregoicoa Limited | Information & communication | 2007 |
| Ahmbach Limited | Administrative & support | 2024 |
| Ahrc Holdings Ltd | Hospitality | 2025 |
| Aislaby Stone Limited | Mining & quarrying | 2002 |
| AJ West Ltd | Wholesale & retail | 2021 |
| AJD Joinery Services Limited | Construction | 2005 |
| AK Westside PLK Limited | Mining & quarrying | 2013 |
| AL Suspension Ltd | Manufacturing | 2019 |
| Alan Atkinson Limited | Construction | 2002 |
| Alan Herbert Ltd | Mining & quarrying | 2012 |
| Albionhallrhb Limited | Hospitality | 2013 |
| Alesowest Limited | Mining & quarrying | 2013 |
| ALL Aspects Contracts Ltd | Construction | 2011 |
| ALL Cyrillic Limited | Professional & scientific | 2025 |
| ALL Whitby Properties Limited | Real estate | 2021 |
| Alum Garth Minerals Ltd | Mining & quarrying | 2012 |
| Alwaste Limited | Water & waste | 2006 |
| Andersons Whitby Ltd | Hospitality | 2023 |
| Andy Bowman Roofcare and Building Ltd | Construction | 2001 |
| Angel Fisheries Harbourside Limited | Hospitality | 2020 |
| Angel Fisheries Limited | Hospitality | 2017 |
| Anros Land Ltd | Real estate | 2012 |
| Apiceutical Research Centre Limited | Professional & scientific | 2011 |
| AR Plumbing & Property Maintenance Ltd | Construction | 2025 |
| Argyle and Welton (Whitby) Limited | Households | 2021 |
| Arncliffe Arms B&B Ltd | Hospitality | 2022 |
| Arncliffe Arms Limited | Real estate | 2010 |
| Arncliffe Property Limited | Real estate | 2011 |
| Art Disco Limited | Wholesale & retail | 2022 |
| Artisan Picture Frames Limited | Wholesale & retail | 2025 |
| Arundel Howe Management Company Limited | Households | 2007 |
| Asaf (Whitby) Ltd | Extraterritorial | 2018 |
| ASH (Fairfield) Holdings Limited | Financial services | 2023 |