| Business | Phone |
| Clayton Business Licenses 6000 Heritage Trl, Clayton 94517 | (925) 673-7310 |
| Clayton City Office 6000 Heritage Trl, Clayton 94517 | (925) 673-7300 |
| Clayton Engineering-Public Wrk 1005 Oak St, Clayton 94517 | (925) 672-9700 |
| Getty Oil Pump Station Marsh Creek Rd, Clayton 94517 | (925) 672-0869 |