When you buy something in an app, the amount is deducted from your operator account balance or added to your operator bill. Pay in one step, or reserve the amount first and charge it after confirmation.
One-step payment: submit the amount and items to add the charge directly to the operator bill.
Two-step payment: reserve the amount first, then charge it after confirmation. You can also cancel.
In a two-step payment, the user enters an SMS verification code if required, then confirms payment after verification.
One step vs. two stepsOne step suits immediate purchases; two steps suit scenarios where stock or service availability must be confirmed first.
Payment statusDuring payment, the operator responds with processing, pending verification, reserved, succeeded, denied, or cancelled.
Carrier Billing: How it works
- Create a paymentThe service provider submits the phone number, amount, currency, item description, and reference number.
- Reserve and confirmA two-step payment uses prepare to reserve the amount, verifies with an SMS code if required, then uses confirm or cancel.
- Add to the billOnce payment is complete, the charge is added to the operator bill and the status becomes succeeded.
Carrier Billing: API spec
POST /paymentsPOST /payments/prepare → if required, POST /payments/{paymentId}/validate → /confirm or /cancelamountTransaction: phone number, amount amount, currency currency, description, referenceCode| Response fields | Meaning | Example |
|---|---|---|
| paymentId | Payment ID | pay-7c1e… |
| paymentStatus | processing, pending_validation, denied, reserved, succeeded, cancelled | succeeded |
| validationInfo.action | Verification action: open or validate | validate |
| paymentDate | Actual payment time | 2026-10-13T10:41:00Z |
Responses for three scenarios (excerpts)
succeededPayment complete, added to the bill150Amount (under amountTransaction.paymentAmount)TWDCurrencyreservedAmount reservedsucceededPayment completepending_validationWaiting for user verificationvalidateEnter the SMS verification code to continueSpec source: CAMARA CarrierBillingCheckOut r3.2 (Carrier Billing v0.5.0)
Carrier Billing: GSMA use cases
One Click Checkout for Visitors
Problem to solveComplicated checkout processes lead to abandoned carts and lost sales.
Carrier Billing's rolePasses a phone number and amount to pay through the operator bill.
GSMA source ↗Passenger Experience
Problem to solveMeets passengers’ varied needs to improve their travel experience.
Carrier Billing's roleOffers a simple way to pay.
Used together: Device Roaming Status, Location Retrieval, Quality on Demand
GSMA source ↗GSMA case studies (1)
Sources: GSMA Open Gateway Use Case Library and API Descriptions (accessed 2026-10-14). Descriptions are summaries.