Source: https://docs.debitura.com/collection-partners/integration-guides/start-a-case

# Start a Case

Transition a case from `PendingVerification` to `Active` via the Collection Partner API.

<a id="overview"></a>

## Overview

When Debitura assigns a case to your agency, it arrives in `PendingVerification`. Once you have verified the details and are ready to begin collection, call `POST /cases/{id}/start` to activate it.

For an explanation of case statuses and the actions available in each, see [Case Status Definitions](https://support.debitura.com/en/articles/13910011-collection-partners-case-status-definitions-and-allowed-actions).

<a id="implementation"></a>

## Implementation

Starting a case requires identifying the actor — the team member whose name appears on the welcome message sent to the creditor. Identify them with **either** `userEmail` **or** `userId`; at least one is required. This is distinct from the assigned user (`assignedUserEmail` / `assignedUserId`), which optionally sets who handles the case ongoing. Retrieve valid team members from [`GET /users`](https://docs.debitura.com/api/collection-partner-api/users.md#lists-team-members-belonging-to-the-authenticated-collection-par) before calling this endpoint.

```http
POST https://collectionpartner-api.debitura.com/cases/{id}/start
XApiKey: YOUR_API_KEY
Content-Type: application/json

{
  "userEmail": "collector@agency.com",
  "welcomeMessage": "We have received your case and will begin collection proceedings.",
  "collectionPartnerReference": "GET-2025-0042",
  "reminderFees": 100.00
}
```

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `userEmail` | string | **Yes\*** | Email of the active team member sending the welcome message. Recommended over `userId`. Use `GET /users` to list valid users |
| `userId` | UUID | **Yes\*** | **Deprecated** — legacy alternative to `userEmail`. Still accepted for backwards compatibility |
| `welcomeMessage` | string | **Yes** | Message sent to the creditor confirming activation (max 5000 chars) |
| `collectionPartnerReference` | string | No | Your internal reference for the case (max 128 chars) |
| `assignedUserEmail` | string | No | Email of the team member assigned to handle the case ongoing. If omitted, no one is assigned — the actor is not used as a fallback |
| `assignedUserId` | UUID | No | **Deprecated** — legacy alternative to `assignedUserEmail` |
| `interestFees` | decimal | No | Interest fees added to the debtor's obligation |
| `reminderFees` | decimal | No | Reminder fees added to the debtor's obligation |
| `collectionFees` | decimal | No | Collection fees added to the debtor's obligation |

\* Provide at least one of `userEmail` or `userId` (`userEmail` takes precedence if both are sent). If neither is supplied, the request returns `400` with error `MissingUserIdentifier`.

**Business context:** See [Additional Fees](https://support.debitura.com/en/articles/13635901-additional-fees-and-charges-interest-late-fees-vat-bank-fees-and-partner-added-fees) for how fees are calculated and applied.

A successful call returns `200 OK`:

```json
{
  "caseId": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "caseReference": "Q8OAXF3W",
  "status": "Active",
  "activatedAt": "2026-02-27T10:15:00Z",
  "collectionPartnerReference": "GET-2025-0042"
}
```

<a id="error-handling"></a>

## Error Handling

| Status | Cause |
| --- | --- |
| `400` | Case is not in `PendingVerification`; neither `userEmail` nor `userId` was provided (`MissingUserIdentifier`); the actor or assigned user is not a valid active team member; `welcomeMessage` is too long; or the case requires custom terms |
| `404` | Case does not exist or is not assigned to your agency |
| `500` | Internal server error |

<a id="whats-next"></a>

## What's Next

Once a case is active, [update case progress](https://docs.debitura.com/collection-partners/integration-guides/update-case-progress.md) to log activities and communicate with the creditor. When a payment is received, [record it](https://docs.debitura.com/collection-partners/integration-guides/record-payments.md) via the API.