| Terry & Thomas Construction Limited | Birmingham | 1975 |
| Terry James Waste Solutions Ltd | Harlow | 2021 |
| TES Environmental Services Limited | Lancashire | 1996 |
| TES Holdings (Wrexham) Limited | Wrexham | 2018 |
| TES Holdings Limited | Haverhill | 2019 |
| Tes-Amm (Europe) Ltd. | Irvine | 2005 |
| Tess OMO Technologies Ltd | Wolverhampton | 2016 |
| Tessmill Limited | Lincoln | 2004 |
| Test Valley Skips Ltd. | Andover | 2012 |
| Test Valley Wetlands Limited | Andover | 2021 |
| Tetbury Upton Water Management Limited | Tetbury | 1999 |
| Tetris-Men Removals Ltd | West Midlands | 2021 |
| Teward Recycling Limited | Darlington | 2013 |
| Texa Threat Solutions Ltd | Huntingdon | 2019 |
| Textek Limited | Whitchurch | 2016 |
| Textile Recycling Solutions Limited | London | 2017 |
| Tezcal Waste Management Ltd | Cannock | 2020 |
| Tezplumbers Ltd | Chelmsford | 2025 |
| TFA Carsales and Recovery Ltd | Bedford | 2019 |
| TG Enterprise Holding Ltd | Cardiff | 2025 |
| TG Industrial Services Limited | Renfrewshire | 2006 |
| TG Waste & Sewerage Limited | Cheltenham | 2020 |
| TGA Sustainability UK Ltd | London | 2022 |
| TGC Ventures Ltd | Beeston | 2017 |
| TGC Zone Plus Ltd | Woodford Green | 2025 |
| Tgme UK Ltd | Watford | 2012 |
| TGW Services Limited | London | 2025 |
| Th&E Home and Garden Services Co Ltd | London | 2025 |
| Thalia Awrp ODC Limited | Manchester | 2014 |
| Thalia IOW ODC Limited | Manchester | 2011 |
| Thalia IOW SPV Limited | Manchester | 2015 |
| Thalia MK ODC Limited | Manchester | 2013 |
| Thalia WB ODC Limited | Manchester | 1969 |
| Thalia WB Services Limited | Manchester | 2007 |
| Thames Aggregates Limited | Barking | 2013 |
| Thames Air & Water Tech Limited | High Wycombe | 2015 |
| Thames Asbestos Removal Ltd | Kidderminster | 2024 |
| Thames Clearance Ltd | Maidenhead | 2024 |
| Thames Recycling Limited | Barking | 2012 |
| Thames Sewage Barge London Limited | London | 2024 |
| Thames Soft Ltd | London | 2025 |
| Thames Tank Cleaning Services Limited | Croydon | 1991 |
| Thames UK Group Limited | Staines-Upon-Thames | 2025 |
| Thames Valley Oils Ltd | Gerrards Cross | 2002 |
| Thames Valley Recycling Limited | Wiltshire | 1998 |
| Thames Valley Skip Hire Ltd | Stoke Mandeville | 2022 |
| Thames Valley Water Services Ltd | Wendover | 2012 |
| Thames Waste Management Ltd | Enfield | 2023 |
| Thames Water Commercial Services Limited | Brighton | 2012 |
| Thames Water Utilities Limited | Reading | 1989 |
| THAMES21 Limited | Gravesend | 2003 |
| Thamesdown Recycling Limited | Swindon | 2022 |
| Thameside Solutions Ltd | Staines-Upon-Thames | 2025 |
| Thanet Recovery Services Limited | Birchington | 2025 |
| Thanet Skip Hire Ltd | Ramsgate | 2023 |
| Thanet Waste Services Limited | Ashford | 1998 |
| Thatcham Skip Hire Limited | London | 2023 |
| THC Plastic Processing Specialists Limited | Belfast | 2015 |
| THE a S G Autocentres Limited | Birmingham | 2009 |
| THE Afterparty Cleaning Co Ltd | Birmingham | 2023 |
| THE Aggregate Factory Ltd | Dalkeith | 2010 |
| THE Alliance for Beverage Cartons and the Environment Limited | Altrincham | 2010 |
| THE Apex Refurbs Ltd | Coventry | 2025 |
| THE Asbestos Group Limited | Brierley Hill | 2025 |
| THE Ayton Water Company Limited | Middlesbrough | 1987 |
| THE BAG Collection Co Ltd | Bristol | 2025 |
| THE Barton Family Holdings Limited | Lancaster | 2013 |
| THE Battery Recycling Company Ltd | Southampton | 2022 |
| THE Best Display Company Limited | London | 1989 |
| THE Best Service Group Ltd | Norwich | 2018 |
| THE Biddulph Grange Sewage Plant Company Limited | Biddulph | 2010 |
| THE Big Shed Limited | Manchester | 2002 |
| THE BIN Co Ltd | Swansea | 2026 |
| THE BIN Guys Ltd | Bristol | 2023 |
| THE BIN Lady and Family Ltd | Milford Haven | 2026 |
| THE Blogg's Ltd | Bishops Waltham, Southampton | 2017 |
| THE Bloggs Enviromental Ltd | Bishops Waltham, Southampton | 2022 |
| THE Blue Harbour Project CIC | Cardiff | 2023 |
| THE Bluebird Clearance Co Limited | Ruislip | 2015 |
| THE Bonspiel Curling Stone Company Limited | East Kilbride | 1959 |
| THE Box King Ltd | Oldham | 2023 |
| THE Bridgewater Canal Company (Supply Services) Limited | Manchester | 2025 |
| THE Brierley Water Company Limited | Leominster | 2005 |
| THE Brookes Management Company Limited | Paignton | 2000 |
| THE Brownfield Consultancy Ltd | Southam | 2012 |
| THE Bury Water Company Limited | Dulverton | 1993 |
| THE Butterfly & CIE Limited | Harrow | 2024 |
| THE Calder Conservation Group CIC | Heckmondwike | 2024 |
| THE Caledonian Golf Group Limited | 20 Castle Terrace | 1998 |
| THE Captain Nemo Limited | St. Helens | 2025 |
| THE Carlyle Services Ltd | Walsall | 2022 |
| THE Chandlers Green Water Company Ltd | Hook | 2003 |
| THE Cleaners Pack Ltd | London | 2025 |
| THE Cleaning Clearing and Driving Company Ltd | Salisbury | 2014 |
| THE Cleanmove Hospitality & Logistics Limited | London | 2025 |
| THE Cleanup Squad Ltd. | London | 2018 |
| THE Clearing Crew Ltd | Bury St. Edmunds | 2025 |
| THE Clearout Crew Caerffili Ltd | Machen | 2025 |
| THE Coffee Recycling Co Ltd | Bolton | 2017 |
| THE Complete Group (LDN) Ltd | Dartford | 2022 |