DocsAPI Reference
Complete API reference for the Cost+ Payment API
The Cost+ Payment API lets you create and manage orders, process payments, handle refunds, and manage payment links.
Base URL
| URL | |
|---|---|
| API | https://api.costplus.online/v1 |
There is no separate sandbox URL. Sandbox vs production mode is determined by the API key — use a key from a sandbox website in the Merchant Portal for testing, or a production website for live transactions.
Authentication
All API requests use HTTP Basic Auth. Use your API key as the username with an empty password:
curl -u {api_key}: https://api.costplus.online/v1/orders/See the Authentication guide for detailed setup instructions.
API Sections
Orders API
Create, retrieve, update, and cancel payment orders. Includes refund, capture, and void operations.
Payment Links API
Create and manage reusable payment links that support multiple payment attempts.
Search API
Search across your orders using flexible criteria.
Self Service API
Manage your project settings and retrieve supported currencies.
Webhooks
Receive real-time notifications when order or transaction statuses change. See the Webhook Event Schemas page for payload details.
Usage Guides
For step-by-step walkthroughs of common integration patterns, see the Guides section:
- Hosted Payment Page — accept payments via redirect
- Recurring Payments — set up subscriptions and scheduled billing
- One-Click Payments — fast checkout for returning customers
- Auth / Capture / Void — two-step payment flows
- Refunds — process full and partial refunds
- Webhooks — receive real-time status notifications
- Payment Links — create reusable payment links