| Business | Phone |
| Merrimac Building Inspector 4 School St, Merrimac 1860 | (978) 346-4066 |
| Merrimac Communication Ctr 16 E Main St, Merrimac 1860 | (978) 346-8321 |
| Merrimac Light Dept 10 W Main St, Merrimac 1860 | (978) 346-8311 |
| Merrimac Selectmens Office 4 School St, Merrimac 1860 | (978) 346-8862 |