> ## Documentation Index
> Fetch the complete documentation index at: https://api.smartlead.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Assign Client to Campaign

> Assign a campaign to a client (or remove its client), optionally applying the client's DNC list

<Note>
  Requires your own API key. Client API keys get `401`.

  Assigning a client also:

  * replaces the campaign's SmartServer assignments with the new client's SmartServers
  * sets the client on the campaign and its subsequences
  * shares the campaign's leads with the new client

  Sub-sequence campaigns cannot be assigned directly. Assign the parent campaign instead.
</Note>

## Query Parameters

<ParamField query="api_key" type="string" required>
  Your SmartLead API key
</ParamField>

## Request Body

<ParamField body="campaignId" type="number" required>
  Campaign ID
</ParamField>

<ParamField body="clientId" type="number | null">
  Client ID to assign. Use `null` to remove the campaign's client.
</ParamField>

<ParamField body="applyClientDNC" type="boolean | null">
  When `true` and `clientId` is set, the client's DNC (block list) is applied to the campaign
</ParamField>

<RequestExample>
  ```bash cURL theme={null}
  curl -X POST "https://server.smartlead.ai/api/v1/campaigns/assign-client?api_key=YOUR_KEY" \
    -H "Content-Type: application/json" \
    -d '{"campaignId": 123, "clientId": 456, "applyClientDNC": true}'
  ```

  ```python Python theme={null}
  import requests

  response = requests.post(
      "https://server.smartlead.ai/api/v1/campaigns/assign-client",
      params={"api_key": "YOUR_API_KEY"},
      json={"campaignId": 123, "clientId": 456, "applyClientDNC": True}
  )
  print(response.json())
  ```
</RequestExample>

## Response Example

<ResponseExample>
  ```json 200 theme={null}
  {
    "ok": true,
    "message": "success",
    "client": {
      "id": 456,
      "email": "client@example.com"
    }
  }
  ```

  ```json 200 - Client removed (clientId null) theme={null}
  {
    "ok": true,
    "message": "success",
    "client": null
  }
  ```

  ```json 500 - Error theme={null}
  {
    "message": "Invalid client Id!"
  }
  ```
</ResponseExample>

Possible `message` values on error: `Invalid campaign Id!`, `Cannot assign client to a sub sequence!`, `Cannot assign the same client to the campaign`, `Invalid client Id!`.