| 00595WB | J.C. Barrett (Electrical) Ltd | YES | YES | Richmond Electrical Wholesale | YES | YES | YES | YES | YES | YES |
| 01132W | J.G. Kelly Supplies Ltd | YES | NO | | N/A | N/A | N/A | YES | YES | YES |
| 01363WB | J.H. Donnelly Ltd | YES | YES | | YES | YES | YES | YES | YES | YES |
| 00340WB | J.J. McQuillan Son & Company Ltd | YES | YES | | YES | YES | YES | YES | YES | YES |
| 01417WB | J.L. Fenton Ltd | YES | YES | | N/A | N/A | N/A | YES | YES | NO |
| 01437W | J.M. Dolan & Co. Ltd | YES | NO | | YES | YES | YES | YES | YES | YES |
| 00668W | J.M.Canty International Ltd | YES | NO | | YES | YES | YES | YES | YES | YES |
| 00507WB | J.P. Distributors Ltd | YES | YES | | YES | YES | YES | YES | YES | YES |
| 01090W | J.V.A. Analytical Ltd | YES | NO | | N/A | YES | YES | YES | YES | Reg-Pending |
| 00692WB | Java Instrument Technologies Ltd | YES | NO | Pac Products | YES | YES | YES | YES | YES | Reg-Pending |
| 01067W | JDM Products | YES | NO | | N/A | Reg-Pending | Reg-Pending | Reg-Pending | Reg-Pending | Reg-Pending |
| 00832W | Jencons (Scientific) Ltd | YES | NO | | N/A | YES | YES | YES | NO | NO |
| 01598W | Jeol(UK) | YES | NO | | NO | NO | NO | NO | NO | Reg-Pending |
| 01206B | Jim Hanley (Farm Machinery) Ltd | NO | YES | | N/A | N/A | N/A | YES | YES | Reg-Pending |
| 01496WB | JML Direct Ltd | YES | YES | | N/A | N/A | N/A | YES | YES | YES |
| 01213B | Joe King Batteries | NO | YES | | N/A | N/A | N/A | YES | YES | YES |
| 01394WB | John Deere Forestry Ltd | YES | YES | John Deere Ltd | N/A | N/A | N/A | N/A | YES | YES |
| 00899WB | John McKenna Lawnmower Spares Ltd | YES | YES | | N/A | YES | YES | YES | YES | YES |
| 00781WB | John Murphy (Castlerea) Ltd | YES | YES | | YES | YES | YES | YES | YES | YES |
| 00879WB | John O'Connor Ronoco Ltd | YES | NO | | YES | YES | YES | WEEE YES | Reg-Pending | NO |
| 00469WB | John Stafford & Sons (Dublin) Ltd | YES | YES | | YES | YES | YES | YES | YES | NO |
| 00541WB | Johnson & Johnson (Ireland) Ltd | YES | YES | | YES | YES | YES | YES | YES | YES |
| 01286W | Johnson & Johnson Vision Care Ireland Ltd | YES | NO | Vistakon Ireland | N/A | N/A | Reg-Pending | Reg-Pending | Reg-Pending | Reg-Pending |
| 00836WB | Johnson Brothers Ltd | YES | YES | | N/A | YES | YES | YES | YES | YES |
| 01401W | Johnson Diversery Ireland Ltd | YES | No | | Reg-Pending | Reg-Pending | Reg-Pending | Reg-Pending | Reg-Pending | NO |
| 00594WB | Joseph Murphy (Ballina) Ltd | YES | YES | Joseph Murphy | YES | YES | YES | YES | YES | YES |
| 01383B | Joyce's Supermarket Ltd | NO | YES | | N/A | N/A | N/A | YES | YES | Reg-Pending |
| 01549B | Jungheinrich Lift Truck Ltd | NO | YES | | N/A | N/A | N/A | YES | YES | YES |
| 00361W | Juniper Networks Ireland | YES | NO | | YES | YES | YES | YES | YES | YES |
| 01092WB | JVC Europe Ltd | YES | YES | JVC Ireland | N/A | N/A | N/A | YES | YES | YES |