| A.P Building Solutions Ltd | Builders | DL1 1JG | 2026 |
| Absass Ltd | Builders | DL1 2RR | 2018 |
| Aburns Engineering Ltd | Builders | DL3 0UN | 2026 |
| Acnz 2022 Ltd | Builders | DL1 2NG | 2022 |
| Advanced Inspections Ltd | Builders | DL3 0SL | 2016 |
| Affordable Homes Group Ltd | Builders | DL3 9AZ | 2015 |
| Ah Property Improvements Ltd | Builders | DL1 1GB | 2022 |
| All Aspect Safety Ltd | Builders | DL1 4LZ | 2025 |
| Allan Oliver Reinforcing Ltd | Builders | DL3 7EH | 1999 |
| Alwyn Doors Ltd | Builders | DL3 7SD | 2023 |
| Amber Grange (Darlington) Ltd | Builders | DL1 5RL | 2013 |
| Amira Construction Ltd | Builders | DL3 7SP | 2025 |
| Andy Hadden Landscaping & Building Services Ltd | Builders | DL1 1GB | 2024 |
| Arnco Building Services Ltd | Builders | DL3 7AR | 2025 |
| Arpent Ltd | Builders | DL1 4QB | 2024 |
| Aspire Property Management Services Ltd | Builders | DL3 7RX | 2025 |
| Atd Renovations Ltd | Builders | DL1 1XF | 2022 |
| Avant Developments Ne Ltd | Builders | DL1 1BJ | 2024 |
| Aw Tiling Ltd | Builders | DL1 3RG | 2019 |
| B & C Building Contractors Ltd | Builders | DL3 9AU | 2012 |
| Bat Home Improvement Ltd | Builders | DL1 4WH | 2026 |
| Bat Home Improvement Services Ltd | Builders | DL1 4WH | 2026 |
| Bd Supplies (Darlington) Ltd | Builders | DL1 5TG | 2019 |
| Blackburn Marshall Construction (Ne) Ltd | Builders | DL1 1RQ | 2011 |
| Blackwell Investments (Ne) Ltd. | Builders | DL1 1GL | 2013 |
| Borthwick Construction Ltd | Builders | DL3 0TW | 2019 |
| Braddan Structures Ltd | Builders | DL1 2PB | 2008 |
| Brass Holdings Ltd | Builders | DL3 7EH | 2023 |
| Broken Homes Ltd | Builders | DL3 0HD | 2025 |
| C & S Paving Services Ltd | Builders | DL3 6QE | 2017 |
| C Hamilton Construction Ltd | Builders | DL1 3SP | 2022 |
| C.T. Steel Site Services Ltd | Builders | DL3 8NE | 2001 |
| Cab Construction North East Ltd | Builders | DL1 1LA | 2024 |
| Castle Homes Maintenance Ltd | Builders | DL1 1YG | 2024 |
| Catterick Property Services Ltd | Builders | DL1 1GB | 2025 |
| Cherry Westfield Ltd | Builders | DL1 4JW | 2021 |
| Chris Banks Windows Ltd | Builders | DL1 4NZ | 2003 |
| Cjf Construction Ne Ltd | Builders | DL1 1JL | 2016 |
| Cl Access Ltd | Builders | DL1 4NT | 2024 |
| Clinton Building Services Ltd | Builders | DL3 0PX | 2020 |
| Cm Site Services Ltd | Builders | DL3 7BJ | 2023 |
| Cobon Validation Ltd | Builders | DL1 3TB | 2025 |
| Commercial Electrical Contractors Ltd | Builders | DL3 7SD | 2025 |
| Commercial Maintenance Contractors Ltd | Builders | DL3 7SD | 2022 |
| County Groundworks Ltd | Builders | DL1 4JD | 2019 |
| Cws Fabs Ltd | Builders | DL3 0ER | 2026 |
| D Wright Groundworks Ltd | Builders | DL3 7BJ | 2017 |
| Daa Groundworks Ltd | Builders | DL3 0XY | 2026 |
| Dagg'S Home Improvements Ltd | Builders | DL1 1GB | 2025 |
| Darlington Door Services Ltd | Builders | DL1 2RR | 1999 |
| Darren Grahams Building Ltd | Builders | DL3 6EN | 2025 |
| David Thornton Landscaping & Property Maintenance Ltd | Builders | DL1 2YY | 2024 |
| Dgb Building Services Ltd | Builders | DL1 3HR | 2016 |
| Dhm Roofing and Building Specialists Ltd | Builders | DL1 5NQ | 2023 |
| Dk Gell Construction Ltd | Builders | DL3 8LF | 2012 |
| Dmw Brickwork Ltd | Builders | DL3 7SD | 2018 |
| Dorserve Ltd | Builders | DL3 7BJ | 2008 |
| Drive-Mac Ltd | Builders | DL1 4HZ | 2024 |
| Dsj Property Maintenance Ltd | Builders | DL1 1GB | 2024 |
| E.A Render Systems Ltd | Builders | DL3 0UN | 2020 |
| Eco Rend North East Ltd | Builders | DL1 2NS | 2012 |
| Electronic Security Solutions Ltd | Builders | DL1 4QD | 2000 |
| Elite Fencing & Property Maintenance Ltd | Builders | DL1 1DY | 2026 |
| Emmanuel General Services Ltd | Builders | DL3 7JT | 2023 |
| Eton Environmental Group Ltd | Builders | DL3 0PH | 2004 |
| Evry Building Solutions Ltd | Builders | DL1 1GB | 2025 |
| Fabfans+ Ltd | Builders | DL1 3RJ | 2025 |
| Factorial Solutions Ltd | Builders | DL3 0HU | 2025 |
| Fdg Services Ltd | Builders | DL1 5TB | 2025 |
| Floorestore Commercial Ltd | Builders | DL1 3HF | 2020 |
| G D Services (N.E.) Ltd | Builders | DL3 7JJ | 2017 |
| G.B.P. (North East) Ltd | Builders | DL3 8TJ | 1999 |
| Gdl Access Ltd | Builders | DL3 7JJ | 2019 |
| George Davo Ltd | Builders | DL1 1DF | 2026 |
| Grayline Tiling Ltd | Builders | DL1 2LD | 2023 |
| H Caldwell Builders Ltd | Builders | DL1 4JY | 2017 |
| H Harrop Contractors Ltd | Builders | DL1 2YF | 2010 |
| H J W Builders Ltd | Builders | DL1 4HH | 2016 |
| Hanafin Estates Ltd | Builders | DL1 1GB | 2017 |
| Harper Building and Maintenance Ltd | Builders | DL1 4LE | 2024 |
| Harrogate Developments Ltd | Builders | DL3 7EH | 2018 |
| Hauxwell Construction Services Ltd | Builders | DL1 4BJ | 2019 |
| Heffs Ltd | Builders | DL3 7AR | 2024 |
| Heritage South Ltd | Builders | DL3 8QJ | 2003 |
| High-Tech Access Ltd | Builders | DL3 7JJ | 2015 |
| Hightech Industrial Rescue Division Ltd | Builders | DL1 4QD | 2026 |
| Hightech Industrial Services Ltd | Builders | DL1 4QD | 2026 |
| Highthorn Developments Ltd | Builders | DL3 7SP | 2018 |
| Hinds Building Services Ltd | Builders | DL1 1GL | 2018 |
| Hssg Inspections Ltd | Builders | DL3 7JJ | 2016 |
| I G Inspection Ltd | Builders | DL3 7JJ | 2019 |
| I.E Finishings Ltd | Builders | DL1 1GB | 2019 |
| Iexpand Developments Ltd | Builders | DL1 1GB | 2016 |
| Ikhs Property Solutions Ltd | Builders | DL1 3ED | 2024 |
| In Charge Construction Ltd | Builders | DL1 4FA | 2019 |
| Iq Building Services Ltd | Builders | DL3 7PR | 2016 |
| Isg Facility Management Ltd | Builders | DL1 2PJ | 2025 |
| J & C Boardline Ltd | Builders | DL3 7SD | 2015 |
| J Foster Building Services Ltd | Builders | DL3 7SD | 2015 |
| J M & A Ramsay (Contracting & Plant Hire) Ltd | Builders | DL1 1GL | 2005 |
| J R Humble Building Services Ltd | Builders | DL3 9DY | 2022 |
| J S Welch Ltd | Builders | DL1 1XL | 2022 |
| J Welch Ltd | Builders | DL1 4JD | 2021 |
| J.P. Hunt Building Contractors Ltd | Builders | DL1 3DF | 2004 |
| Ja Working At Height Ltd | Builders | DL1 3EA | 2023 |
| James Cameron Joinery Ltd | Builders | DL3 7SD | 2019 |
| Jamie Bryant Rope Access Ltd | Builders | DL3 7JJ | 2019 |
| Jay'S Technical Services Ltd | Builders | DL3 7BJ | 2016 |
| Jhc Grounworks Ltd | Builders | DL1 1GB | 2021 |
| Jonny Smith Surveying Services Ltd | Builders | DL1 4JF | 2015 |
| Jordan Wingfield Construction Ltd | Builders | DL1 1LA | 2023 |
| Jsa Rope Access Ltd | Builders | DL3 8LX | 2019 |
| Kes Design Ltd | Builders | DL3 7EH | 2024 |
| Kestrel Kitchen Installations Ltd | Builders | DL3 9AU | 2022 |
| Key 4 Services Ltd | Builders | DL1 1GL | 2024 |
| Key Interiors Ltd | Builders | DL1 2EP | 2015 |
| Keystone Architectural Surveying and Developments Ltd | Builders | DL3 7RG | 2024 |
| Kinship Developments Ltd | Builders | DL1 1DF | 2025 |
| L&C Construction Ltd | Builders | DL1 1GB | 2021 |
| Lc13 Groundworks Ltd | Builders | DL1 4NR | 2022 |
| Lineside Fencing Ne Ltd | Builders | DL1 3LZ | 2021 |
| Lt Access & Maintenance Ltd | Builders | DL3 0SB | 2025 |
| M James Technical Services Ltd | Builders | DL1 2DU | 2023 |
| M&M Total Property Services Ltd | Builders | DL3 7BJ | 2019 |
| Map Building & Roofing Ltd | Builders | DL1 1GY | 2018 |
| Marple'S Property Ltd | Builders | DL1 1XH | 2025 |
| Matthew J Brown Ltd | Builders | DL3 0QF | 2020 |
| Mds Joinery & Building Ltd | Builders | DL3 9EW | 2014 |
| Metro Ceramics Ltd | Builders | DL1 4JW | 2006 |
| Middle East Holding Ltd | Builders | DL1 4DE | 1893 |
| Ml Driveways-Patios & Groundworks Ltd | Builders | DL1 1GB | 2023 |
| Mmb Properties Ltd | Builders | DL1 3TF | 2001 |
| Mph Electrical Contractors Ltd | Builders | DL3 7HJ | 2019 |
| Mulholland Builders Ltd | Builders | DL3 8SE | 2020 |
| Neasham Solutions Ltd | Builders | DL1 2PU | 2025 |
| Nesbitt Security Systems Ltd | Builders | DL1 2FA | 2023 |
| Newalldevelopmentgroup Ltd | Builders | DL1 1GB | 2024 |
| Next Level Construction Services Ltd | Builders | DL1 1GB | 2024 |
| Nicoll Sub Contractors Ltd | Builders | DL1 4RZ | 2025 |
| North East Property Projects Ltd | Builders | DL1 5EA | 2009 |
| Nova Construction & Site Services Ltd | Builders | DL3 7BJ | 2025 |
| Nu-Interiors Ltd | Builders | DL1 2GB | 2013 |
| Oakdale Building and Construction Ltd | Builders | DL1 4DG | 2026 |
| Oakwood Construction (Darlington) Ltd | Builders | DL3 7SD | 2008 |
| Oceanex Ltd | Builders | DL1 1GL | 2011 |
| Offshore Access Solutions Ltd | Builders | DL1 3HQ | 2026 |
| Olympia Property Solutions Ltd | Builders | DL3 8QF | 2024 |
| Opdoc Ltd | Builders | DL3 8NA | 2016 |
| Paul Townend Ltd | Builders | DL3 7SD | 2026 |
| Paul Wilson Construction Ltd | Builders | DL1 5EF | 2023 |