Nitromule
Validate shipping addresses in Nitromule
Updated 2026-09-07
On this page
Address validation checks whether a ship-to (or ship-from) looks deliverable before you spend postage. Accepting corrections early prevents failed deliveries and empty rate shops.
When validation runs
Validation may run when you:
- Enter or edit an address on Get Label or an order
- Import store orders with incomplete street data
- Call the Integrations API
POST /addresses/validate(developers) - Use MCP
nm_validate_address
You can also fix addresses reactively when rates fail or a carrier rejects the label.
What good addresses include
- Street number and name
- Unit / apartment / suite when the building has one
- City, state, and ZIP that match
- Accurate country
- Recipient name suitable for carrier delivery notices
PO Boxes often work with USPS but can block UPS and FedEx. If only USPS rates appear, check whether the address is a PO Box or similar.
Steps — validate while shipping
- Start typing the ship-to address and pick an autocomplete suggestion when it matches the destination.
- If Nitromule or the carrier suggests a corrected address, compare it to what the buyer gave you.
- Accept the correction when it is clearly the same location (standardized spelling, ZIP+4, suite formatting).
- Reject / edit manually when the suggestion points to a different building or city.
- Re-run get rates after any address change.
Common correction types
| Suggestion | Typical meaning |
|---|---|
| Street spelling / suffix | “St” vs “Street”, corrected orthography |
| ZIP+4 or ZIP change | Postal standardization for the same street |
| Secondary unit required | Missing Apt/Suite — add the unit from the order |
| Commercial vs residential | May affect UPS/FedEx price even when deliverable |
Military, territories, and special formats
- APO / FPO / DPO addresses need the correct city/state fields carriers expect
- US territories may rate differently; confirm the country/territory field
- International addresses need postal codes and province fields as required by the destination
When validation fails on these, format carefully rather than forcing a mainland US pattern.
Store order tips
- WooCommerce and eBay imports bring buyer addresses as entered at checkout — spot-check Incomplete orders before buying postage
- If buyers omit apartments, contact them before labeling
- After you correct an address on the Nitromule order, place the order from that corrected order so tracking still syncs
API and automation
Developers should validate before POST /rates and POST /shipments. See API quickstart and OpenAPI POST /addresses/validate.
Troubleshooting
Symptom-focused guide: Troubleshoot address validation.
Still seeing returns to sender? Confirm the return address can receive packages and that the ship-to unit number was present on the label.