| 1 | Eirgrid Public LIMITED Company | Ireland | Dublin | Legal Department | Dublin | D04 FW28 | eirgrid.***** | 2001 | $1,235,036,740 | 610 | N/A | N/A | 338522 |
| 2 | Kirby Group Engineering Unlimited Company | Ireland | Limerick | Raheen Business Park | Limerick | V94 NNC4 | kirbygroup.***** | 1964 | $455,768,983 | 1,158 | N/A | N/A | 41839 |
| 3 | Netgear International LIMITED | Ireland | Cork | 6th Floor, Penrose Two | Cork | T23 YY09 | netgear.***** | 2005 | $438,760,000 | 46 | N/A | N/A | 409506 |
| 4 | Aramark Ireland Holdings LIMITED | Ireland | Dublin | Newenham House | Dublin | D17 AY61 | aramark.***** | 2000 | $341,171,230 | 4,889 | N/A | N/A | 324452 |
| 5 | Specialist Technical Engineering Services Unlimited Company | Ireland | Waterford | Block 10 Cleaboy Business Park | Waterford | N/A | stsgroup.***** | 2006 | $308,773,678 | 749 | N/A | N/A | 432334 |
| 6 | Cooper Industries Trading Unlimited Company | Ireland | Dublin | Eaton House 30 Pembroke Road | Dublin | D04Y0C2 | N/A | 1988 | $164,477,000 | 30 | N/A | N/A | 128031 |
| 7 | Sensori Facilities Management LIMITED | Ireland | Dublin 15 | Plaza 211, Blanchardstown Corporate | Dublin | D15 AP2D | N/A | 2014 | $87,877,294 | 423 | N/A | N/A | 548567 |
| 8 | Veolia Energy Ireland Public LIMITED Company | Ireland | Dublin | Suite 18 Plaza 256 | Dublin | D15TR96 | veolia.***** | 1999 | $82,927,192 | 364 | N/A | N/A | 314060 |
| 9 | Murphy Process Engineering LIMITED | Ireland | Newbridge | Great Connell | Kildare | W12 HD61 | N/A | 1990 | $81,362,287 | 85 | N/A | N/A | 165132 |
| 10 | Actavo (ireland) LIMITED | Ireland | Dublin | Westland Park | Dublin | N/A | N/A | 1985 | $69,141,369 | 353 | N/A | N/A | 105844 |
| 11 | Castle Electrical Factors LIMITED | Ireland | Dublin | 94/96 Middle Abbey Street | Dublin | D01 W8N7 | cefltd.***** | 2007 | $62,924,662 | 98 | N/A | N/A | 438619 |
| 12 | Chubb Ireland LIMITED | Ireland | Blackrock | 2 Stillorgan Industrial Park | Dublin | A94 A2C4 | chubb.***** | 1968 | $44,994,078 | 183 | N/A | N/A | 27640 |
| 13 | Kcc Architectural & Security Supplies LIMITED | Ireland | Dublin | Westgate Business Park | Dublin | D24 TE28 | kccarchitectural.***** | 1998 | $42,259,307 | 202 | N/A | N/A | 296075 |
| 14 | Asgard Cleanroom Solutions LIMITED | Ireland | Kilkenny | Unit E Sark Business Park | Kilkenny | R95 D882 | asgard.***** | 2000 | $32,437,645 | 64 | N/A | N/A | 319316 |
| 15 | Obelisk Communications LIMITED | Ireland | Cavan | Cavan Enterprise Centre | Cavan | H12 W6X5 | obelisk.***** | 1996 | $30,128,419 | 181 | N/A | N/A | 257021 |
| 16 | F. G. Wilson Engineering (dublin) LIMITED | Ireland | Dublin | Block P Ballymount Cross Industrial Estate | Dublin | D12 Y066 | fgwilson.***** | 1978 | $30,112,249 | 28 | N/A | N/A | 65882 |
| 17 | Instrotec LIMITED | Ireland | Westport | Castlebar Road Sheroe | Mayo | N/A | instrotec.***** | 2000 | $28,980,176 | 294 | N/A | N/A | 323855 |
| 18 | Anglo Irish Refrigeration Company LIMITED | Ireland | Ashbourne | Unit 1 Ashbourne Industrial Estate | Meath | A84 HE39 | N/A | 1976 | $26,918,529 | 121 | N/A | N/A | 56305 |
| 19 | Dominic Smith Electrical LIMITED | Ireland | Gorey | Unit 1 Knockmullen Retail Park | Wexford | Y25 WP80 | dominicsmithelectrical.***** | 2006 | $25,230,964 | 72 | N/A | N/A | 419327 |
| 20 | Electric Skyline LIMITED | Ireland | Claremorris | Crf House | Mayo | F12 N2Y2 | electricskyline.***** | 2007 | $24,791,647 | 106 | N/A | N/A | 440831 |
| 21 | M. & L. Manufacturing LIMITED | Ireland | Drogheda | Unit 4 | Louth | A92 WF38 | mlmanufacturing.***** | 1975 | $24,788,915 | 61 | N/A | N/A | 52454 |
| 22 | Brian Healy Electrical LIMITED | Ireland | Newport | Church Street | Mayo | N/A | N/A | 2009 | $23,864,181 | 54 | N/A | N/A | 470050 |
| 23 | Colin Burke Electrical LIMITED | Ireland | Ardrahan | Rahealy | Galway | H91 X8RK | colinburkeelectrical.***** | 2002 | $23,850,495 | 116 | N/A | N/A | 351970 |
| 24 | J. Vaughan Electrical Contractors LIMITED | Ireland | Dublin | Unit 2 Northwest Business Centre | Dublin | D15 VA06 | jve.***** | 1983 | $23,482,686 | 94 | N/A | N/A | 241986 |
| 25 | Tritech Electrical LIMITED | Ireland | Dublin | Clonlara House Clonlara Road | Dublin | D22 | ske.***** | 2008 | $22,358,505 | 50 | N/A | N/A | 456483 |
| 26 | Electroking LIMITED | Ireland | Dublin | The Hyde Building the Park, Unit 2 | Dublin | N/A | N/A | 1997 | $22,204,096 | 27 | N/A | N/A | 259201 |
| 27 | Ltes LIMITED | Ireland | Navan | Drumsillagh | Meath | N/A | N/A | 2015 | $21,779,738 | 133 | N/A | N/A | 573597 |
| 28 | John Fletcher LIMITED | Ireland | Portlaoise | The Courthouse | Laois | R32 H6RK | fletchershardware.***** | 1968 | $21,503,042 | 66 | N/A | N/A | 27553 |
| 29 | Mid-Cork Electrical LIMITED | Ireland | Cork | Lissarda Industrial Park | Cork | P14 YN56 | N/A | 1987 | $21,332,746 | 13 | N/A | N/A | 127408 |
| 30 | Pure Electrical LIMITED | Ireland | Limerick | Unit 52 Eastlink Business Park | Limerick | V94RP40 | finucaneselectrical.***** | 2012 | $21,278,551 | 96 | N/A | N/A | 517521 |
| 31 | Automated Systems & Controls LIMITED | Ireland | Cork | Lissarda Industrial Park | Cork | N/A | N/A | 1994 | $20,573,851 | 42 | N/A | N/A | 222146 |
| 32 | Priority Engineering Services LIMITED | Ireland | Naas | Cedar Lodge | Kildare | W23 FK31 | N/A | 2018 | $19,784,906 | 27 | N/A | N/A | 634588 |
| 33 | Cantwell Electrical Engineering LIMITED | Ireland | Thurles | Graigue | North Tipperary | E41 K8F5 | cantwell.***** | 1981 | $19,556,175 | 44 | N/A | N/A | 81030 |
| 34 | Kiernan Electrical (ireland) LIMITED | Ireland | Ballygarvan | Unit 15 Airport East | Cork | T12 YY17 | kiernanelectrical.***** | 1993 | $19,016,497 | 128 | N/A | N/A | 200303 |
| 35 | Md Electrical Installations LIMITED | Ireland | Ballybofey | Suite 2 | Donegal | N/A | mdeinstallations.***** | 1990 | $18,596,523 | 120 | N/A | N/A | 414157 |
| 36 | Rotary M. & E. Services (ireland) LIMITED | Ireland | Dublin 3 | Esmonde Avenue | Dublin | N/A | N/A | 1962 | $18,378,046 | 166 | N/A | N/A | 19325 |
| 37 | Jmc Electrics Engineering LIMITED | Ireland | Dublin 24 | Suite 5144 | Dublin | N/A | N/A | 2016 | $17,579,085 | 108 | N/A | N/A | 583798 |
| 38 | Daltech Solutions LIMITED | Ireland | Dublin 12 | Unit 7 Western Parkway Business Centre | Dublin | D12FR59 | N/A | 2011 | $17,403,973 | 73 | N/A | N/A | 506821 |
| 39 | J.O.L. Electrical LIMITED | Ireland | Dublin | Suite 212 | Dublin | D24 PPT3 | crosselectrical.***** | 2006 | $17,028,854 | 80 | N/A | N/A | 430956 |
| 40 | Adt Fire And Security LIMITED | Ireland | Dublin | 9a Beckett Way | Dublin | N/A | adt.***** | 1986 | $15,295,718 | 60 | N/A | N/A | 46603 |
| 41 | Tokheim Ireland LIMITED | Ireland | Dublin 22 | L1 | Dublin | N/A | tsgcharge.***** | 1983 | $15,263,944 | 65 | N/A | N/A | 122567 |
| 42 | Mcsherry Electrical LIMITED | Ireland | Mallow | Mallow Industrial Estate | Cork | P51 DX59 | mse.***** | 1989 | $14,986,852 | 64 | N/A | N/A | 118873 |
| 43 | Tim Kelly (electrical Contractors) LIMITED | Ireland | Ballinrobe | Claremorris Road | Mayo | F31 RW66 | timkellygroup.***** | 1980 | $14,368,273 | 120 | N/A | N/A | 76735 |
| 44 | Manning And Buckley Electrical LIMITED | Ireland | Dublin | 174 Skellig House, Mayor Street, Ifsc | Dublin | D01 | mab.***** | 2004 | $13,729,535 | 88 | N/A | N/A | 394773 |
| 45 | Reliable Security Products LIMITED | Ireland | Drumcondra | 1-3 Cian Park Industrial Estate | Cavan | D09 HY04 | rspl.***** | 1993 | $13,381,011 | 24 | N/A | N/A | 201687 |
| 46 | J.J. Dwyer Electrical LIMITED | Ireland | Cork | Southside Industrial Estate | Cork | N/A | dwyers.***** | 1974 | $13,237,369 | 71 | N/A | N/A | 326953 |
| 47 | Richfield Windfarm (roi) LIMITED | Ireland | Blackrock | 8/10 Rockhill, Main Street | Dublin | N/A | N/A | 1999 | $12,769,525 | 5 | N/A | N/A | 317385 |
| 48 | Avonmore Electrical Company LIMITED | Ireland | Mallow | Roskeen | Cork | P51 R206 | avonmore-electrical.***** | 1992 | $11,596,300 | 100 | N/A | N/A | 188529 |
| 49 | Sean Ahern LIMITED | Ireland | Cork | 16 South Link Park | Cork | T12 KD29 | ahernelec.***** | 1970 | $11,035,571 | 68 | N/A | N/A | 31583 |
| 50 | Niedax Cms (cable Management Systems) LIMITED | Ireland | Dublin | 46 Fitzwilliam Square | Dublin | D02 | niedax.***** | 2009 | $9,623,370 | 30 | N/A | N/A | 478617 |
| 51 | Ifes Electrical Services LIMITED | Ireland | Ovens | Wood Road | Cork | N/A | ifes.***** | 2002 | $9,542,693 | 59 | N/A | N/A | 353409 |
| 52 | Action Alarms LIMITED | Ireland | Dublin | Unit C1 Three Rock | Dublin | D18 H6Y8 | N/A | 1981 | $9,217,313 | 71 | N/A | N/A | 81741 |
| 53 | G4s Monitoring (IRE.) LIMITED | Ireland | Dublin 12 | G5 Calmount Business Park | Dublin | D12 T651 | N/A | 1981 | $4,051,215 | 5 | N/A | N/A | 84511 |
| 54 | Sensormatic Electronics CORPORATION (ireland) LIMITED | Ireland | Cork | Albert Quay House | Cork | T12 E102 | N/A | 1995 | $3,478,890 | 343 | N/A | N/A | 214997 |
| 55 | Hannons Holdings LIMITED | Ireland | Roscommon | Racecourse Road | Roscommon | N/A | N/A | 1990 | $3,478,890 | 156 | N/A | N/A | 155604 |
| 56 | Pjk Precision Engineering LIMITED | Ireland | Newbridge | Ladytown | Kildare | W12 VN23 | N/A | 2021 | $3,478,890 | 30 | N/A | N/A | 686629 |
| 57 | M.C.M. Security LIMITED | Ireland | Cork | Mcm Security | Cork | T45 C951 | mcmsecurity.***** | 1985 | $3,478,890 | 30 | N/A | N/A | 109333 |
| 58 | Dan Murphy Electrical LIMITED | Ireland | Mallow | Blueford | Cork | P51 F5PD | N/A | 2008 | $3,478,890 | 30 | N/A | N/A | 452853 |
| 59 | Scan Alarms And Security Systems (UK) LIMITED | Ireland | Dublin | Unit 63, Western Parkway Business Centre, Ballymount Road | Dublin | D12 | N/A | 1982 | $3,478,890 | 30 | N/A | N/A | 909288 |
| 60 | John Kelly & Sons Electrical Services LIMITED | Ireland | Roscommon | Knocknacunny | Roscommon | N/A | N/A | 1977 | $3,478,890 | 30 | N/A | N/A | 59143 |
| 61 | Rtv LIMITED | Ireland | Dublin | Unit 19 Beech Lawn Industrial Estate | Dublin | D12 | N/A | 1986 | $3,478,890 | 30 | N/A | N/A | 117711 |
| 62 | Northstone Construction LIMITED | Ireland | Blackrock | Holly Park Studio, the Old Courtyard | Dublin | N/A | N/A | 2016 | $3,478,890 | 30 | N/A | N/A | 580291 |
| 63 | Cubic-Modulsystem A/S | Ireland | Dublin | 64/65 Parkwest Enterprise Centre | Dublin | N/A | N/A | 1995 | $3,478,890 | 30 | N/A | N/A | 903616 |
| 64 | L. Lynch & CO. (group) LIMITED | Ireland | Dublin | Unit 16 Fonthill Industrial Park | Dublin | D22 P2T4 | leolynch.***** | 1997 | $3,478,890 | 30 | N/A | N/A | 268985 |
| 65 | Dornan Engineering Germany LIMITED | Ireland | Cork | 10 Eastgate Avenue | Cork | T45 PC63 | dornan.***** | 2009 | $3,478,890 | 30 | N/A | N/A | 467883 |
| 66 | Videnda Distribution LIMITED | Ireland | Dublin | 2011 Orchard Avenue | Dublin | D24 HT91 | videnda.***** | 2002 | $3,478,890 | 30 | N/A | N/A | 353696 |
| 67 | Ledtronika (ireland) LIMITED | Ireland | Letterkenny | Sprackburn Cottage High Road | Donegal | N/A | N/A | 2022 | $3,478,890 | 30 | N/A | N/A | 713955 |
| 68 | Designer Engineering EMEA LIMITED | Ireland | Dublin 11 | 52 Nore Road | Dublin | N/A | N/A | 2001 | $2,170,245 | 3 | N/A | N/A | 350768 |
| 69 | Emh Technical Services LIMITED | Ireland | Cork | Emh Technical Services Ltd, Unit 22 Ballyvolane Commercial Park | Cork | T23 K281 | N/A | 2020 | $2,114,613 | 16 | N/A | N/A | 669184 |
| 70 | Prolectric LIMITED | Ireland | Dublin | Lake | Dublin | N/A | N/A | 2021 | $1,382,042 | 16 | N/A | N/A | 709402 |
| 71 | Dh Renewables LIMITED | Ireland | Dundalk | First Floor, Block One Quayside Business Park | Louth | A91 DP8R | N/A | 2022 | $1,194,141 | 5 | N/A | N/A | 718384 |
| 72 | Smart Control Systems LIMITED | Ireland | Dublin | Madoc House | Dublin | D12 EY6T | smartcontrolsystems.***** | 2001 | $1,059,160 | 12 | N/A | N/A | 337020 |
| 73 | Curragh Technology LIMITED | Ireland | Limerick | Block H Lock Quay Service Station | Limerick | V94 CFA4 | N/A | 1990 | $922,508 | 7 | N/A | N/A | 904069 |
| 74 | Snc-Lavalin Engineering And Construction Ireland LIMITED | Ireland | Clonmel | Unit 9, Crann Ard Business Centre | North Tipperary | N/A | N/A | 1957 | $899,000 | 2 | N/A | N/A | 16476 |
| 75 | Skyline Electrical Maintenance Contractors LIMITED | Ireland | Navan | Athboy | Meath | N/A | N/A | 2013 | $739,757 | 6 | N/A | N/A | 522367 |
| 76 | Eco West Electrical And Energy Services LIMITED | Ireland | Westport | Roonith | Mayo | N/A | N/A | 2013 | $696,209 | 2 | N/A | N/A | 530669 |
| 77 | Eleco Fire & Security LIMITED | Ireland | Killarney | Gortshanafa | Kerry | V93H227 | N/A | 2009 | $644,636 | 2 | N/A | N/A | 471748 |
| 78 | O'shea's Electrical LIMITED | Ireland | Cork | Euro Business Park | Cork | T45 WF80 | joneseng.***** | 1981 | $579,815 | 987 | N/A | N/A | 81666 |
| 79 | Hpl Engineering Services LIMITED | Ireland | Drogheda | 24 Laurence Street | Louth | N/A | N/A | 2020 | $579,815 | 180 | N/A | N/A | 679455 |
| 80 | Cloncad LIMITED | Ireland | Moyvalley | Cloncad | Kildare | W91 CS5N | N/A | 2006 | $579,815 | 104 | N/A | N/A | 430596 |
| 81 | Donal Corcoran Electrical LIMITED | Ireland | Callan | Unit 4 Westcourt Business Park | Kilkenny | N/A | excelelect.***** | 2004 | $579,815 | 98 | N/A | N/A | 380333 |
| 82 | Cross Electrical LIMITED | Ireland | Kilmacthomas | Greenan | Waterford | X42 WY67 | crosselectrical.***** | 2017 | $579,815 | 87 | N/A | N/A | 613055 |
| 83 | Vision Security Group LIMITED | Ireland | Dublin | Suite 6 Plaza 256 | Dublin | D02 NY19 | N/A | 1999 | $579,815 | 60 | N/A | N/A | 905558 |
| 84 | Gilmore & Clarke (electrical) LIMITED | Ireland | Cootehill | Rakane | Cavan | N/A | gilmoreclarke.***** | 1998 | $579,815 | 50 | N/A | N/A | 279626 |
| 85 | Brian King Engineering LIMITED | Ireland | Ashbourne | Unit 2 Ashbourne Business Centre | Meath | A84 PT63 | bke.***** | 1992 | $579,815 | 45 | N/A | N/A | 193682 |
| 86 | Longacre Electrical LIMITED | Ireland | Ashbourne | Turnpike House | Meath | A84AH96 | bke.***** | 2010 | $579,815 | 45 | N/A | N/A | 482916 |
| 87 | E. Clarke (castletown-Geoghegan) LIMITED | Ireland | Mullingar | Castletown | West Meath | N91 FH76 | N/A | 1988 | $579,815 | 44 | N/A | N/A | 127888 |
| 88 | Cosgrove Electrical Services LIMITED | Ireland | Dublin | 220 Block C Blanchardstown Corporate Park 2 | Dublin | D15 V2WA | cosgroveelectrical.***** | 2001 | $579,815 | 43 | N/A | N/A | 347196 |
| 89 | Apollo Electrical LIMITED | Ireland | Cabra | Unit 304 Easy Business Centres Ltd Broombridge Station | Dublin | D07 | N/A | 2017 | $579,815 | 43 | N/A | N/A | 611375 |
| 90 | O'hara & Harrison LIMITED | Ireland | Letterkenny | Sprackburn Cottage | Donegal | F92 D580 | oharaharrison.***** | 2001 | $579,815 | 42 | N/A | N/A | 338579 |
| 91 | C.J. Ryder Lawlor LIMITED | Ireland | Dublin | Unit C4 Santry Business Park | Dublin | D09 AE84 | cjryderlawlor.***** | 1982 | $579,815 | 42 | N/A | N/A | 91049 |
| 92 | Seamus Byrne Electrical LIMITED | Ireland | Carlow | Wexford Road Business Park | Carlow | R93 R2R3 | sbe.***** | 1985 | $579,815 | 41 | N/A | N/A | 109102 |
| 93 | Micheál Healy Electrical LIMITED | Ireland | N/A | 4 Killowenbeg | Co. Kerry | N/A | N/A | 2017 | $579,815 | 40 | N/A | N/A | 613474 |
| 94 | Sword Security LIMITED | Ireland | Dublin | 1 Morehampton Square | Dublin | D04 DV50 | N/A | 2012 | $579,815 | 40 | N/A | N/A | 907496 |
| 95 | William Farrell LIMITED | Ireland | Dublin | Unit 3 | Dublin | D12 E023 | wfl.***** | 1985 | $579,815 | 36 | N/A | N/A | 108895 |
| 96 | Dominic Fleming Electrical Accessories LIMITED | Ireland | Dublin | Unit 2 Damastown Walk | Dublin | D15 PNN4 | dfe.***** | 2000 | $579,815 | 33 | N/A | N/A | 330497 |
| 97 | H.v.s.m. LIMITED | Ireland | Ashbourne | Unit 3/4 Ash Court | Meath | A84 FF97 | hvsm.***** | 1990 | $579,815 | 33 | N/A | N/A | 166896 |
| 98 | Clarke Electrical Engineering LIMITED | Ireland | Bailieborough | Lisnalea | Cavan | A82 F4W8 | N/A | 2000 | $579,815 | 32 | N/A | N/A | 319072 |
| 99 | Wizer Energy LIMITED | Ireland | Cork | Unit 16-18 Ballytrasna Park | Cork | T45 HT98 | N/A | 2020 | $579,815 | 31 | N/A | N/A | 680390 |
| 100 | King & Moffatt Connected LIMITED | Ireland | Carrick-on-shannon | Attirory Business Park | Leitrim | N41 XE98 | N/A | 2019 | $579,815 | 31 | N/A | N/A | 652108 |