> For the complete documentation index, see [llms.txt](https://doc.bunq.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.bunq.com/tutorials/your-first-payment/creating-the-api-context/start-a-session.md).

# Start a Session

Sessions provide **temporary authentication**, meaning that even if a session token is exposed, it will automatically expire after a set period. This balances security with usability—developers don’t need to constantly re-authenticate, but access remains limited to prevent long-term misuse. The session timeout can be adjusted in the bunq app, giving users control over their security settings. This session-based approach is common in **high-security environments**, ensuring that access is time-limited and reducing persistent threats.

Once you have a session we'll return you the user object. So you have all details of your user.

The response of the session API call is a object with a **session token**, this is the token we'll use in subsequent requests to authenticate requests. There is also a **userid** in this response. Which we will use in the next calls.

```json

{
    "Response": [
        {
            "Id": {
                "id": 25536694
            }
        },
        {
            "Token": {
                "id": 25536694,
                "created": "2025-03-05 16:12:11.918100",
                "updated": "2025-03-05 16:12:11.918100",
                "token": "ce717e3001d979ff5e22bac13508b46e7ad740971d1d75c5371614e546ca8b83"
            }
        },
        {
            "UserPerson": { "id": 1822179,
                            "rest of the user object":...  }
        }
    ]
}

```

{% hint style="info" %}
**If your session expires you simply call the /session-server endpoint again. This gives you a new session token to use**
{% endhint %}

{% openapi src="/files/xJ3v0GinyfONRbxz8Srh" path="/session-server" method="post" %}
[swagger.json](https://346554585-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FGE9Y1hc6C24r4Hen6KFH%2Fuploads%2Fgit-blob-218d6e618d396b5e315e30f903e92e143f7a4cc1%2Fswagger.json?alt=media)
{% endopenapi %}

### What's next:

You'll see that with the session we obtained the details of your user. If you look closely you can see that the [User](/basics/bunq-api-objects/user.md) object is also returned with this call. If you're still using Postman it's a good idea to already note the user ID as that is used in many of the subsequent API calls.

Up next we'll set up this user object so that you can use it in your sandbox.


---

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