> For the complete documentation index, see [llms.txt](https://docs.finpay.id/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.finpay.id/api-reference/finpay-pg/core-api/virtual-account/open-payment.md).

# Open Payment

```mermaid
sequenceDiagram
    actor Customer
    participant Merchant
    participant Finpay
    participant Bank

    Customer->>Merchant: Choose payment method Bank Virtual Account
    Merchant->>Finpay: request API openpayment/register "va..."
    
    opt inform va number to channel
        Finpay->>Bank: request Create VA
        Bank-->>Finpay: response Create VA
    end
    
    Note over Finpay: insert va number
    Finpay-->>Merchant: response API openpayment/register "va..."
    Merchant-->>Customer: Show VA Number
    
    Customer->>Bank: Pay VA Bank
    Bank->>Finpay: inquiry
    Finpay-->>Bank: response
    Bank->>Finpay: payment
    Finpay-->>Bank: response
    
    Note over Finpay: flagging success
    Finpay->>Merchant: Callback Notification
    Merchant-->>Customer: Show payment success
```


---

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