USPS Rates & Labels changelog
All notable changes to USPS Rates & Labels (kv_usps_v3) are documented here.
The format follows Keep a Changelog and the project uses Semantic Versioning.
[Unreleased]
Section titled “[Unreleased]”[1.0.0] - 2026-11-05
Section titled “[1.0.0] - 2026-11-05”- Real-time shipping service “USPS (new APIs)” on the USPS APIs platform (OAuth 2.0, Shipping Options 3), replacing the retired Web Tools API on CS-Cart 4.17 and 4.18 and working next to the 4.21 USPS module.
- 21 USPS services: domestic, flat rate envelopes and boxes, international and Global Express Guaranteed (rates).
- Per-method retail / commercial / contract prices, markup, rounding, free shipping threshold, fallback rate, delivery estimate, Signature Confirmation.
- Box presets, automatic box choice, packaging weight, dimensional weight hint; rate cache shared by all USPS methods.
- Domestic and international labels (Labels 3, International Labels 3, Payments 3) in PDF, ZPL or PNG with customs forms and remembered HS codes; shipment with tracking number created automatically.
- Void unused labels and request refunds for manifested labels.
- Tracking (Tracking 3) on the order and in the customer account, cron updates, optional order status on delivery.
- Address validation (Addresses 3) with suggestions at checkout and on the order page.
- Multi-Vendor: marketplace-owner or vendor label mode with per-vendor USPS accounts and vendor-panel labels.
- Encrypted credentials and tokens, API log with masked secrets, USPS test environment switch.