Post Offices List in Clayton City, New York:
| Clayton Post Office | 236 John St, Clayton, NY 13624 |
| Frontenac Post Office | 15749 Round Is, Clayton, NY 13624 |
| Grenell Post Office | 16498 Grenell Is, Clayton, NY 13624 |
| Murray Isle Post Office | 42650 Murray Is, Clayton, NY 13624 |