Create an international shipping label with the required customs form data using the USPS International Labels 3.0 API
domain: developers.usps.com · 6 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Register a USPS APIs account and obtain OAuth 2.0 client credentials via the USPS APIs platform
Exchange client credentials for an access token before calling any labels endpoint
Submit package characteristics, mail class (e.g., Priority Mail International), and customs declaration content items to the International Labels 3.0 endpoint
Retrieve the generated label image along with the electronically filed customs form data
Verify the response confirms the Shipping Services File was created so the item is compliant before induction
Update any legacy Web Tools XML integration to the new OAuth-based v3 request/response schema using USPS's field mapping guide
Known gotchas
USPS retired the legacy Web Tools APIs in January 2026, so Basic Auth-based international label integrations must already be migrated to this OAuth-based v3 endpoint
Field names and request structure differ from the legacy XML Web Tools API; a direct 1:1 mapping is not guaranteed for every element
Customs content item detail (description, value, HS tariff number where applicable) is validated server-side and incomplete data will reject the label request
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