| 2 EXCEL ENGINEERING LIMITED | Lasham | A rating |
| 24 Seven Civil Engineering Ltd | Harrow | A rating |
| 2H Offshore Engineering Ltd | Woking | A rating |
| 3K's Engineering Company Limited | Llanelli | A rating |
| A Squared Engineering Ltd | Perth | A rating |
| A-squared Studio Engineers Ltd | London | A rating |
| A.V. ATKINSON (FOURWAYS) LTD. | Sandhurst | A rating |
| A&B Engineering (Electrical Service Division) Limited | Liverpool | A rating |
| A&B Engineering (Mechanical Service Division) Limited | Liverpool | A rating |
| A2 Engineering Ltd | Crawley | A rating |
| AARAA ENGINEERING LTD | London | A rating |
| Aarsleff Ground Engineering Ltd | Newark on Trent | A rating |
| ABBOTTSWAY ENGINEERING LTD | london | A rating |
| ABD Engineering & Development LTD | Essex | A rating |
| ABMI Engineering UK Ltd | London | A rating |
| Ace Engineering Solutions Ltd | London | A rating |
| ACE UK ENGINEERING CONSULTANTS LTD | Reading | A rating |
| Acoustic & Engineering Consultants Limited | Stockport | A rating |
| ACRON ENGINEERING SERVICES (UK) LTD | London | A rating |
| ACS COMMERCIAL RISK ENGINEERING LTD | Manchester | A rating |
| Acuity Engineering Limited | Corby | A rating |
| Aden Engineering & Consultancy Ltd | Birmingham | A rating |
| Adept Consulting Engineers | Leeds | A rating |
| ADI Facilities Engineering | Birmingham | A rating |
| ADMC ENGINEERING LTD | London | A rating |
| ADP Consulting & Engineering Ltd | London | A rating |
| Advance engineering uk ltd | kings lynn | A rating |
| Advanced Compressor Engineering Services Limited | Wallingford | A rating |
| Advanced Engineering Group Ltd | OMAGH | A rating |
| Advansys Engineering Services and Consultancy Limited | Camberley | A rating |
| AEROSPACE ENGINEERING SOLUTIONS LTD | BRAINTREE | A rating |
| Affinity Fire Engineering (UK) Limited | London | A rating |
| AGEMA ENGINEERING LTD | COVENTRY | A rating |
| Agile Engineering Consultancy Ltd | Frognall | A rating |
| Aidan Strain Electrical Engineering Ltd (ASEE Ltd) | Mullaghbawn | A rating |
| AIM ENGINEERS LTD | Bristol | A rating |
| Airbus Belfast Limited | Belfast | A rating |
| Airbus Defence and Space Limited | Portsmouth | A rating |
| Airbus Helicopters UK Limited | Kidlington | A rating |
| Airbus Operations Limited | Bristol | A rating |
| Airbus Protect Limited | Bristol | A rating |
| Aircraft Engineering Services Limited | Stansted | A rating |
| AJ Engineering & Construction Services Limited | Forres | A rating |
| AKN Engineering Limited | Bishop's Stortford | A rating |
| Alfred Cheyne Engineering Ltd | Turriff | A rating |
| All Pipe Engineering Limited | Northen Ireland | A rating |
| ALLIANCE DESIGN UK LTD T/A EDGE CONSULTING ENGINEERS | MANCHESTER | A rating |
| Allied Global Engineering Ltd | Glossop | A rating |
| ALMA ENGINEERING CO LTD | BEDFORSHIRE | A rating |
| Alpha Building Services Engineering Ltd | London | A rating |
| ALPHA ENGINEERS LTD | LONDON | A rating |
| Alpine Fire Engineers Ltd | BURY | A rating |
| Alstom Engineering and Services Limited | Derby | A rating |
| Altair Engineering Ltd | Leamington Spa | A rating |
| AM Civil Engineering Services Ltd | Belfast | A rating |
| AMF Precision Engineering Limited | Bromborough | A rating |
| AMS Nuclear Engineering Ltd | Bridgwater | A rating |
| Anam Engineering LTD | London | A rating |
| Andrews Associates Engineers Ltd | Croydon | A rating |
| Andun Engineering Consultants Ltd | Nottingham | A rating |
| Anel Engineering & Contracting Limited | Chester | A rating |
| Anglia Precision Engineering Ltd | Peterborough | A rating |
| Apex Consulting Engineers Limited | Sheffield | A rating |
| Apex Lift and Escalator Engineers Limited | Bexleyheath | A rating |
| Applied Laser Engineering Ltd | Walton-on-Thames | A rating |
| Apuljack Engineering | East Brent | A rating |
| ARC Engineering LTD | Ilford | A rating |
| Armada Engineering Ltd | Falmouth | A rating |
| Armadillo Engineering (UK)Ltd | Radstock | A rating |
| Ascendion Engineering Solutions Europe Limited | London | A rating |
| Asco Engineering Ltd | Skelmersdale | A rating |
| ASKAM CIVIL ENGINEERING LTD | Lancaster | A rating |
| ASME Engineering Ltd | Harrow | A rating |
| Aspecto Power Engineering Ltd. | Warwick | A rating |
| AT Engine Controls Ltd T/A ATEC Engineering Solutions | Manchester | A rating |
| ATAK ENGINEERING UK LTD | London | A rating |
| Athena Engineering Limited | Preston | A rating |
| Atkins & Potts Ltd | Newbury | A rating |
| Atkins Brickwork Limited | Chessington | A rating |
| Atkins Walters and Webster Limited | Bristol | A rating |
| ATKINS WAY STORE | HINCKEY | A rating |
| AtkinsRealis PPS Limited | London | A rating |
| AtkinsRealis UK Limited | London | A rating |
| Autoflame Engineering Limited | Kent | A rating |
| Automated Engineering Services (UK) Limited | London | A rating |
| Avan Engineering Services LTD | Bushey | A rating |
| AVVSJ Engineers Ltd | Birmingham | A rating |
| Axi Design & Engineering Ltd | Hull | A rating |
| Axiom Engineering Associates Limited | Stockton on Tees | A rating |
| B and A Precision Engineering Limited | Preston | A rating |
| Babcock & Wilcox Volund Limited | London | A rating |
| Babcock Defence & Security Holdings LLP | London | A rating |
| Babcock International Limited | London | A rating |
| Babcock Training Limited | Cosham | A rating |
| Babcock Wanson UK Limited | Borehamwood | A rating |
| Bachmann Electrical Engineering Ltd. | Birmingham | A rating |
| BADITECH ENGINEERING AND CONSULTANCY LTD | NEWARK | A rating |
| BAE Systems OneArc UK Limited | Farnborough | A rating |
| BAE Systems Plc | London | A rating |
| BAEL LIMITED | Bournemouth | A rating |
| Bakken & Baeck Ltd | London | A rating |
| Balfour Beatty Group Employment Limited | London | A rating |
| Barkers Engineering Limited | Fenton | A rating |
| Barrett Mahony Consulting Engineers UK Ltd | London | A rating |
| BARTON FIRTOP ENGINEERING CO LIMITED | Kidderminster | A rating |
| BCA Engineering Supplies Ltd | England | A rating |
| BdR Civil & Structural Engineering Limited | Hadlow | A rating |
| Be Safe Engineering Service Ltd | HOUNSLOW | A rating |
| Bechtel Limited | London | A rating |
| Beck & Pollitzer Engineering Limited | Burton | A rating |
| BEETA ENGINEERING LTD | Pinner | A rating |
| BERMONDSEY ENGINEERING & TRADE CO. LTD | London | A rating |
| Beyond Engineering Consulting Ltd | Wembley | A rating |
| BG&E Consulting Engineers Ltd | London | A rating |
| BGB Engineering Ltd | Grantham | A rating |
| BIMTech Engineering Limited | Manchester | A rating |
| Birchfield Engineering Limited | Dudley | A rating |
| BIZ Engineering Limited | Ensfield | A rating |
| BJD CONSULTING ENGINEERS LTD | London | A rating |
| Black and White Engineering Limited | Newcastle upon Tyne | A rating |
| Blackrow Engineering Co Ltd | Grimsby | A rating |
| Blackwood Engineering Ltd | Aberbeeg | A rating |
| BlueBinaries Engineering and Solutions Ltd | Woking | A rating |
| Blueprint Design Engineering Limited | Ulverston | A rating |
| BOARDMAN ENGINEERING AND MANAGEMENT SERVICES LTD | Nottingham | A rating |
| Boslan Engineering Limited | Cambridge | A rating |
| Bowers Electrical Engineering Services Limited | Northampton | A rating |
| Box Twenty Consulting Engineers Ltd | Bristol | A rating |
| Bradstock Consulting Engineers Ltd | Edenbridge | A rating |
| Brafe Engineering | ipswich | A rating |
| Bridges Electrical Engineers Ltd | Midsomer Norton | A rating |
| Brighter Green Engineering | High Wycombe | A rating |
| BRIT ENGINEERING SERVICES LTD | Dunstable | A rating |
| British Airways Engineering Gatwick Limited | West Sussex | A rating |
| British Engineering Services Ltd | Warrington | A rating |
| British Rema Rotary Engineering Ltd | Chesterfield | A rating |
| Broadway Engineering Ltd | Bristol | A rating |
| Browne Jacobson LLP | Nottingham | A rating |
| Bruce Engineering Services NI Ltd | COOKSTOWN | A rating |
| BTS ENGINEERING LTD | Grangemouth | A rating |
| Building Design Engineering Limited | Cheltenham | A rating |
| Building Engineering Services Association | London | A rating |
| Buro Happold Engineers Limited | Bath | A rating |
| Byland Engineering Limited | York | A rating |
| C&R Design LTD t/a AMA Consulting Engineers | Barnet | A rating |
| CAE ENGINEERING & ARCHITECTURE LTD | Bournemouth | A rating |
| Cairn Cross Civil Engineering Limited | Morley, Leeds | A rating |
| Caldwell Consulting Engineers Limited | Belfast | A rating |
| CALIBER ENGINEERING SERVICES UK LTD | Brentford | A rating |
| Callatech Precision Engineers Ltd | WORTHING | A rating |
| Carbon Plan Engineering | Huddersfield | A rating |
| Cardinal Engineering Ltd | Crawley | A rating |
| Carmichael Engineering & Consulting Limited | Thame | A rating |
| Cascade Aerospace Engineering Ltd | Camberley | A rating |
| CD International Building Services Engineers Limited | London | A rating |
| CE Turner Engineers Ltd | Melton Mowbray | A rating |
| Centum Engineering Services UK Ltd | The Creagh | A rating |
| Chad Engineering UK Ltd | Windsor | A rating |
| Chandos Civil Engineering Ltd | Cheadle | A rating |
| Charles & Associates Consulting Engineers | Aylesford | A rating |
| Charles & Associates Consulting Engineers Ltd | Aylesford | A rating |
| Charles Scott & Partners Consulting Engineers Limited | GLASGOW | A rating |
| Charlesworth Engineering Ltd | Lisburn | A rating |
| China Harbour Engineering Company (UK) Ltd | London | A rating |
| CHPK Fire Engineering Limited | London | A rating |
| Cilantro Engineering UK | London | A rating |
| CITY ENGINEERING LIMITED | London | A rating |
| Civcon Civil Engineering Ltd | Leeds | A rating |
| Civic Engineers Ltd | Manchester | A rating |
| CIVIL AND STRUCTURAL ENGINEERING SHETLAND LIMITED | Tingwall | A rating |
| Civil Engineering Crew Limited | Birmingham | A rating |
| Civile Engineering Ltd | Lincoln | A rating |
| Civinity Engineering UK Ltd | Gillingham | A rating |
| CKK Civil Engineering Limited | Southend On Sea | A rating |
| Clayton Precision Engineering Co.Ltd | Isleworth | A rating |
| Cleantech Engineering Limited | Edenbridge | A rating |
| CMT Engineering Limited | Cradley Heath | A rating |
| CNA CONSTRUCTION & ENGINEERING LTD | Sittingbourne | A rating |
| Co Lab Engineering Limited | Whitehaven | A rating |
| COMPLIANCE ENGINEERING LIMITED | Antrim | A rating |
| COMVE ENGINEERS LTD | London | A rating |
| Concept Engineering Consultants Ltd | Leicester | A rating |
| Conquip Engineering Group | Alton | A rating |
| Consarc Engineering Ltd | Holytown | A rating |
| CONSERVE ENGINEERING SOLUTIONS UK LTD | Liverpool | A rating |
| Consulting Engineers Group UK Limited | Southampton | A rating |
| Consulting Structural Engineers Limited | Guildford | A rating |
| Continental Engineering Services Limited | Lichfield | A rating |
| Control Electrical Engineers Ltd | London | A rating |
| Convery Engineering Ltd | Kilrea | A rating |
| Coote Engineering Ltd | Ballygawley | A rating |
| Core Engineering Consulting Group Limited | London | A rating |
| Cortex Engineering Solutions Ltd | Dungannon | A rating |
| Costain Limited | London | A rating |
| Cottam & Brookes Engineering Co (1985) Limited | Caerphilly | A rating |
| Crafter Engineering Limited | Warrington | A rating |
| Create Consulting Engineers Ltd | Norwich | A rating |
| CT Engineering Group UK Limited | Bristol | A rating |
| Cummins Civil Engineering Ltd | Knutsford | A rating |
| Currock Engineering Company Ltd. | Chelmsford | A rating |