The city of Johns Island is assigned specific ZIP Code(s) by the United States Postal Service (USPS) to make mail delivery accurate and efficient. A ZIP Code in Johns Island helps identify the correct postal area, ensuring that letters, parcels, and packages reach the right neighborhood or post office without delay. For residents, businesses, and visitors, knowing the correct Johns Island ZIP Code is important not only for mailing purposes but also for location-based services, navigation, and demographic reference.
| Post Office | Johns Island |
| County | Charleston |
| State | South Carolina |
| ZIP Code | 29455 |
| Post Office | Johns Island |
| County | Charleston |
| State | South Carolina |
| ZIP Code | 29457 |