| Business | Phone |
| A & F Electrical Testing Inc 11 Hillcrest Dr, Smithtown 11787 | (631) 584-5625 |
| Advantage Electric 38 Ledgewood Dr, Smithtown 11787 | (631) 543-1276 |
| Live Wire Electric Co 30 Baylor Dr, Smithtown 11787 | (631) 724-8252 |
| Louis Piekut Electric Inc 43 Colonial Rd, Smithtown 11787 | (631) 366-0774 |
| Cheyenne Electrical Corp 8 Creek Rd, Smithtown 11787 | (631) 366-4666 |
| Momern Electrical Contractors 550 Smithtown Byp, Smithtown 11787 | (631) 863-0747 |
| Newhoff Electrical Inc 8 Ridge Rd, Smithtown 11787 | (631) 979-5117 |
| G M Gebhardt Elect Contractor 2 Landing Meadow Rd, Smithtown 11787 | (631) 979-6644 |
| Gessin Electrical Contractors 550 Smithtown Byp, Smithtown 11787 | (631) 863-3025 |
| R De Masi Electric Corp 597 Landing Ave, Smithtown 11787 | (631) 361-5106 |
| Rak Electrical Inc 1025 W Jericho Tpke, Smithtown 11787 | (631) 543-7450 |
| K V Electric Inc 18 Poplar Dr, Smithtown 11787 | (631) 724-4758 |
| Rla Electric 9 Kingfisher Dr, Smithtown 11787 | (631) 724-4868 |
| Shore To Shore Electrical Corp Smithtown 11787 | (631) 265-1615 |
| Stony Brook Electric Inc 191 Juniper Ave, Smithtown 11787 | (631) 265-5826 |