A specific data attribute provided by the United States Postal Service (USPS) that identifies whether a delivery address is classified as residential or business (commercial).
While it originated as a technical flag in the USPS database, it has become a vital tool for e-commerce and logistics companies to accurately calculate shipping costs and choose the most cost-effective carrier.
Why RDI Exists
The distinction between a home and a business is critical because of how different carriers structure their pricing:
- Private Carriers (UPS, FedEx, etc.): These companies typically apply a residential surcharge because delivering to a home is more expensive for them (fewer packages per stop, longer distances between houses, and more residential-only navigation).
- USPS: The Postal Service generally does not charge extra for residential delivery because it is already required to visit every household daily.
By using RDI, a business can rate shop in real-time. If the RDI flag says Residential, the business might choose USPS to avoid the private carrier’s $4.00–$5.00 surcharge.
RDI Attributes
| Feature | Description |
| Data Source | Exclusively provided by the USPS via their Address Management System (AMS). |
| Status Codes | Typically returned as Y (Residential), N (Business/Commercial), or M (Mixed). |
| Certification | RDI data is usually accessed through CASS-certified (Coding Accuracy Support System) software. |
| Zoning vs. Use | Unlike some private carriers who classify based on city zoning, USPS RDI is based on the actual use of the delivery point. |
Business Benefits
- Cost Optimization: Avoids unexpected residential surcharges that private carriers bill after the package has already been sent.
- Marketing Accuracy: Helps businesses segment their mailing lists (e.g., sending a Home Improvement catalog only to residential RDI addresses).
- Fraud Prevention: Identifying a residential address 1 a red flag for manual review.
- Carrier Selection: Automated shipping software uses RDI to dynamically route packages to the cheapest carrier based on the address type.
The Home Office Nuance
One of the biggest challenges RDI solves is the home-based business. A private carrier might see a neighborhood and automatically flag it as residential. However, if the USPS has that specific address registered as a commercial delivery point, the RDI flag will reflect that, potentially saving the shipper money on commercial rates.
