Accept a payment from a customer who hasn’t paid through PayNext before. The SDK handles payment method collection, validation, and 3D Secure authentication automatically.
When to Use
| Scenario | Guide |
|---|
| New customer, first payment | This guide |
| Returning customer, saved payment method | Charge Returning Customers |
Prerequisites
Before accepting payments:
- PayNext account with API keys (Testing & Sandbox)
- Processor connected in Dashboard → Integrations
- Plan created in Dashboard → Plans (defines amount and currency)
- Payment methods enabled in Dashboard → Checkout
Integration
Follow the SDK Quickstart to:
Create a client session
Call POST /client-session from your server with customer email and plan ID.
Mount the SDK
Initialize checkout with the session id as clientToken.
Handle the result
Use onCheckoutComplete and onCheckoutFail callbacks.
The SDK Quickstart includes complete code examples for Next.js and vanilla TypeScript, plus optional optimizations like preloading.
What Happens Next
After a successful first payment:
- Customer created in PayNext with saved payment method
- Payment method stored securely for future charges
- Subscription started (if using a recurring plan)
For subsequent charges, use Charge Returning Customers to leverage the saved payment method. 
