> For the complete documentation index, see [llms.txt](https://docs.verifone.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.verifone.com/support-nordics/v400m/how-tos/how-to-locate-the-serial-number.md).

# How to Locate the Serial Number

Find the serial number on your V400M — on the label underneath, or in the terminal menu.

{% hint style="info" %}
**Use this when** you need your terminal's serial number — for example, when setting up the terminal or contacting Verifone Support.
{% endhint %}

You can find the serial number in two ways:

{% tabs %}
{% tab title="On the label" %}

1. Carefully turn the terminal over so you can see the underside.
2. The **serial number** is printed on the label on the **underside** of the terminal.
   {% endtab %}

{% tab title="In the menu" %}

1. Press **4** and **6** at the same time, then enter password **1234** and press the **green button**.
2. Select **Terminal information**.
3. Select **Version information**.
4. Select **Hardware**.
5. The **serial number** is shown here.
6. Press the **red button** to close the menu.
   {% endtab %}
   {% endtabs %}

<details>

<summary>Keywords</summary>

Also called: serial number, S/N, find serial number, terminal serial, device serial. Search terms: serial number, S/N, underside, label, terminal information, version information, hardware, V400M.

</details>


---

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