# POST /invoices/:invoice_id/cancel-installments

**Resource:** [Invoices](./invoices.md)  
**MCP tool:** `cancel_invoice_installments`  
**Scopes:** `invoices:write`  
**Write operation:** yes

Stop the instalments on a native invoice. If the client has started a plan, no further payments are taken; what was paid stays paid and the invoice keeps its remaining balance (installment_status becomes cancelled). If no plan has started yet, instalments are switched off and the pay link offers pay in full only.

## Parameters

| Name | In | Type | Required | Description |
|------|----|------|----------|-------------|
| `invoice_id` | path | string | yes |  |
| `require_approval` | body | boolean | no | Optional. Set true to route this write into the approval queue for human review instead of executing it immediately (returns 202 + an approval_id). Works even when your key/token has permission to execute directly. |

## Request example

```bash
curl -X POST   "https://api.trustpager.com/functions/v1/api/v1/invoices/:invoice_id/cancel-installments"   -H "Authorization: Bearer YOUR_API_KEY"   -H "Content-Type: application/json"   -d '{"require_approval":"..."}'
```

---
Base URL: `https://api.trustpager.com/functions/v1/api/v1` — Auth: `Authorization: Bearer YOUR_API_KEY`