UMS (China UMS)
Channel Overview
China UMS (银联商务) is the comprehensive payment institution under China UnionPay. DaxPay integrates UMS in direct mode (channel ums_pay); one onboarding accepts WeChat, Alipay, and QuickPass collection, with certificate-free signing — one of the simplest channels to configure.
UMS and UnionPay (QuickPass, channel
union_pay) are two independent channels; see UnionPay - Difference from UMS for the comparison.
Payment Products
UMS splits into 6 payment products by collection scenario; pick one when creating the channel merchant:
| Product | Scenario | Accepted methods |
|---|---|---|
ums_qrcode (C-scan-B) | User scans the merchant's QR code | Aggregate QR, WeChat QR, Alipay QR, UnionPay QR |
ums_barcode (B-scan-C) | Merchant scans the user's payment code | UnionPay barcode |
ums_h5 (H5) | Mobile browser payment | WeChat H5, Alipay H5, UnionPay H5 |
ums_jsapi (Official Account) | Inside WeChat / Alipay | WeChat JSAPI, Alipay JSAPI |
ums_mini (mini-program) | Inside a mini-program | WeChat mini-program, Alipay JSAPI |
ums_app (APP) | Inside the merchant app | WeChat APP, Alipay APP |
Configuration Structure
- Create the channel merchant: Merchant Workbench → Channel Merchants → Create, pick the scenario product and fill in merchant name + UMS merchant number (mid);
- Configure keys (Channel Merchant Detail → Key Configuration):
| Field | Notes |
|---|---|
| Environment | Production / sandbox |
| Terminal number | tid, assigned by the service provider |
| App ID | App identifier on the UMS open platform |
| App key | Signs API requests (HmacSHA256) |
| Communication key | Verifies async notifications |
Callback Handling
- Payment and refund async notifications are verified with the communication key and acknowledged;
- Callback URLs are generated by the platform; no per-merchant configuration in the UMS console.
Notes
- No certificates needed — the app key plus communication key complete the integration;
- Bank card and gateway acquiring require separate activation with UMS;
- WeChat / Alipay JSAPI scenarios require app configuration on the corresponding platform first.