| Business | Phone |
| Barnwell County Assessor 57 Wall St # 221, Barnwell 29812 | (803) 541-1011 |
| Barnwell County Auditor 57 Wall St, Barnwell 29812 | (803) 541-1040 |
| Barnwell County Tax Collector 57 Wall St, Barnwell 29812 | (803) 541-1048 |
| Barnwell County Treasurer 57 Wall St # 123, Barnwell 29812 | (803) 541-1050 |
| Delinquent Tax Collector 57 Wall St # 121, Barnwell 29812 | (803) 541-1024 |