| Business | Phone |
| Madison-Chatham Sewage Trtmnt N Passaic Ave, Chatham 7928 | (973) 635-4616 |
| Chatham Administrative Offices 54 Fairmount Ave, Chatham 7928 | (973) 635-0674 |
| Chatham Borough Engineer 54 Fairmount Ave, Chatham 7928 | (973) 635-5443 |
| Chatham Building Inspector 58 Meyersville Rd, Chatham 7928 | (973) 635-5622 |
| Chatham Construction Code 54 Fairmount Ave, Chatham 7928 | (973) 635-5507 |
| Chatham Twp Administration Office 58 Meyersville Rd, Chatham 7928 | (973) 635-4600 |
| Chatham Twp Engineering 58 Meyersville Rd, Chatham 7928 | (973) 635-3204 |