| 1 | John Sisk & Son | €1,485,700,000 | €715,500,000 | €770,200,000 | General Building, Civil Engineering |
| 2 | Mercury | €1,480,000,000 | €600,000,000 | €880,000,000 | Mechanical & Electrical Engineering |
| 3 | Jones Engineering | €930,000,000 | €558,000,000 | €372,000,000 | Mechanical, Electrical, Process Engineering |
| 4 | Winthrop | €658,447,244 | €234,122,533 | €424,324,711 | General Contractor |
| 5 | BAM Ireland | €633,000,000 | €560,000,000 | €73,000,000 | General Building, Civil Engineering |
| 6 | John Paul Construction | €544,000,000 | €420,000,000 | €124,000,000 | General Building, Civil Engineering |
| 7 | Collen Construction | €500,000,000 | €222,000,000 | €278,000,000 | General Building |
| 8 | Kirby Group Engineering | €402,699,261 | €253,446,397 | €149,252,864 | Mechanical & Electrical Engineering |
| 9 | PJ Hegarty & Sons UC | €375,000,000 | €340,000,000 | €35,000,000 | General Building, Civil Engineering |
| 10 | Dornan | €370,000,000 | €105,000,000 | €265,000,000 | Mechanical & Electrical Engineering |
| 11 | Bennett | €320,000,000 | €250,000,000 | €70,000,000 | General Building |
| 12 | Walls Construction | €303,000,000 | €303,000,000 | – | General Building |
| 13 | JJ Rhatigan & Company | €263,300,000 | €202,200,000 | €61,100,000 | General Building |
| 14 | STS Group | €255,000,000 | €85,000,000 | €170,000,000 | Electrical Engineering |
| 15 | Suir Engineering | €242,000,000 | €175,000,000 | €67,000,000 | Mechanical & Electrical Engineering |
| 16 | Designer Group | €202,300,000 | €125,426,000 | €76,874,000 | Mechanical & Electrical, Process Engineering |
| 17 | Wills Bros | €163,000,000 | €82,000,000 | €81,000,000 | General Building, Civil Engineering |
| 18 | Murphy Ireland | €158,000,000 | €136,000,000 | €22,000,000 | General Building, Civil Engineering |
| 19 | mac-group | €144,500,000 | €102,000,000 | €42,500,000 | General Building, Fit-outs |
| 20 | Ardmac Group Ltd | €130,196,965 | €70,071,985 | €60,124,980 | General Building |
| 21 | King & Moffatt Building Services | €129,000,000 | €36,000,000 | €93,000,000 | Mechanical & Electrical Engineering |
| 22 | Conack Construction Ltd | €122,000,000 | €122,000,000 | – | General Building |
| 23 | Monami Construction | €106,000,000 | €106,000,000 | – | General Building |
| 24 | SIAC Construction Group | €96,000,000 | €90,000,000 | €6,000,000 | General Building, Civil Engineering |
| 25 | Flynn | €95,725,517 | €77,505,447 | €18,220,070 | General Building |
| 26 | Clancy | €95,721,578 | €95,721,578 | – | General Building |
| 27 | Jons Civil Engineering Company Ltd | €92,000,000 | €92,000,000 | – | Civil Engineering |
| 28 | Radley Engineering Ltd | €88,448,641 | €87,012,069 | €1,436,572 | Mechanical Fabrication & Installation |
| 29 | Duggan Brothers (Contractors) Ltd | €87,000,000 | €87,000,000 | – | General Building |
| 30 | Townmore | €84,000,000 | €56,000,000 | €28,000,000 | General Building |
| 31 | Elliott Building & Civil Engineering Ltd | €75,000,000 | €60,000,000 | €15,000,000 | General Building, Civil Engineering |
| 32 | Glan Agua MEIC | €70,276,378 | €51,751,663 | €18,524,715 | General Building, Civil Engineering |
| 33 | Stewart | €67,000,000 | €67,000,000 | – | General Building |
| 34 | Purcell Construction | €65,900,000 | €65,900,000 | – | General Building |
| 35 | MMD Construction (Cork) Ltd | €64,660,000 | €64,660,000 | – | General Building |
| 36 | Vision Contracting Ltd | €63,500,000 | €63,500,000 | – | General Building |
| 37 | BMD & Co Ltd | €62,700,000 | €62,700,000 | – | Mechanical, Electrical, Process Engineering |
| 38 | ABM Group | €61,500,000 | €44,000,000 | €17,500,000 | General Building, Civil Engineering |
| 39 | Coffey Group | €52,700,000 | €52,700,000 | – | Civil Engineering |
| 40 | Ganson Building & Civil Engineering Contractors Ltd | €50,077,982 | €41,456,806 | €8,621,176 | General Building, Civil Engineering |
| 41 | MSL Engineering Ltd | €47,405,655 | €46,077,245 | €1,328,410 | Mechanical Engineering |
| 42 | Gem Group | €47,240,000 | €47,240,000 | – | General Building, Specialist Joinery Contracting |
| 43 | Adston Group Holdings Ltd | €46,262,062 | €14,207,696 | €32,054,366 | General Building |
| 44 | T&I Fitouts Ltd | €46,000,000 | €46,000,000 | – | Main Contractor, Fit-outs |
| 45 | DFL | €45,432,782 | €35,274,808 | €10,157,974 | General Building |
| 46 | Lynskey Engineering Ltd | €44,622,000 | €21,141,000 | €23,481,000 | Mechanical Engineering |
| 47 | CJK Engineering | €44,546,326 | €44,546,326 | – | Mechanical & Electrical Engineering |
| 48 | Clonmel Enterprises Ltd | €44,439,802 | €44,439,802 | – | General Building, Civil Engineering |
| 49 | Leo Lynch | €44,270,000 | €44,270,000 | – | Mechanical & Electrical Engineering |
| 50 | Arkil Holding Ltd, (Arkil Ltd and Park Plant Hire Ltd) | €43,920,000 | €43,890,000 | €30,000 | Civil Engineering |
| 51 | LMC Group Ltd | €42,000,000 | €41,160,000 | €840,000 | M&E Contracting, Specialist Offsite Contractor |
| 52 | Kilcawley Building & Civil Engineering (Sligo) Ltd | €40,000,000 | €40,000,000 | – | General Building, Civil Engineering |
| 53 | Tritech Engineering | €36,000,000 | €36,000,000 | – | Mechanical & Electrical Engineering |
| 53 | Mannings Construction Ltd | €36,000,000 | €21,100,000 | €14,900,000 | General Building |
| 55 | Glenbeigh Construction | €35,332,678 | €35,332,678 | – | General Building |
| 56 | Mythen Construction | €34,822,950 | €34,822,950 | – | General Building |
| 57 | Townlink | €30,000,000 | €30,000,000 | – | General Building |
| 58 | Shareridge | €28,527,000 | €28,527,000 | – | General Building |
| 59 | Weltec Engineering | €26,700,564 | €26,700,564 | – | Mechanical & Electrical Engineering |
| 60 | ClearyDoyle | €25,000,000 | €25,000,000 | – | General Building |
