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

# Shift4Shop

This guide explains how to add Sezzle as a payment option on your Shift4Shop website, enabling customers to use Sezzle at checkout.

<Warning>
  Only 3D Cart legacy merchants can use Sezzle at the moment.
</Warning>

### Install the Sezzle Shift4Shop Extension

1. Log in to your website's Shift4Shop admin
2. Get the [app](https://apps.shift4shop.com/sezzle)
3. Copy and paste your Store URL into the input area, then click `Proceed`

   <Frame>
     <img src="https://mintcdn.com/sezzle/WWvtQJ-zXjzjnMaw/images/docs/plugins/shift4shop/1-authorization-request.png?fit=max&auto=format&n=WWvtQJ-zXjzjnMaw&q=85&s=5a2991f4cc4eaf352d233ee06c0e07f3" alt="1 Authorization Request Pn" width="622" height="346" data-path="images/docs/plugins/shift4shop/1-authorization-request.png" />
   </Frame>
4. Check the PCI Compliance box, then click `Acknowledge and Authorize the App` to start the installation

### Admin Configuration

1. In your Shift4Shop admin, go to Settings > Payment
2. Click Select Payment Methods

   <Frame>
     <img src="https://mintcdn.com/sezzle/WWvtQJ-zXjzjnMaw/images/docs/plugins/shift4shop/2-settings-payment.png?fit=max&auto=format&n=WWvtQJ-zXjzjnMaw&q=85&s=6121758b1445eee7c36aad5810943a71" alt="2 Settings Payment Pn" width="1918" height="759" data-path="images/docs/plugins/shift4shop/2-settings-payment.png" />
   </Frame>
3. Turn the `Sezzle` switch to `On`
4. Copy your Public Key from your [Sezzle Merchant Dashboard](https://dashboard.sezzle.com/merchant/settings/apikeys)
   * Paste it into the corresponding field in the Sezzle configuration page of your Shift4Shop admin
5. Next to Private Key, click `Change`
6. Copy your Private Key from your [Sezzle Merchant Dashboard](https://dashboard.sezzle.com/merchant/settings/apikeys)
   * Paste it into the corresponding field in the Sezzle configuration page of your Shift4Shop admin
7. Click `Save`

   <Frame>
     <img src="https://mintcdn.com/sezzle/WWvtQJ-zXjzjnMaw/images/docs/plugins/shift4shop/3-sezzle-keys.png?fit=max&auto=format&n=WWvtQJ-zXjzjnMaw&q=85&s=50ebb589f84953b56173d410430009d3" alt="3 Sezzle Keys Pn" width="1873" height="446" data-path="images/docs/plugins/shift4shop/3-sezzle-keys.png" />
   </Frame>
8. To restrict Sezzle usage by country, click the `Exclude List` hyperlink under the `Sezzle` switch
9. Click `Add Location`
10. Select the desired country, then click `Add`

    <Frame>
      <img src="https://mintcdn.com/sezzle/WWvtQJ-zXjzjnMaw/images/docs/plugins/shift4shop/4-exclude-list.png?fit=max&auto=format&n=WWvtQJ-zXjzjnMaw&q=85&s=6b2945221d02921b3df8f3110186a965" alt="4 Exclude List Pn" width="1878" height="601" data-path="images/docs/plugins/shift4shop/4-exclude-list.png" />
    </Frame>

<Note>
  Installation is complete!
</Note>

### Validate

Step through a [test checkout](/docs/api/test-cards#checkout-testing) to validate the integration is properly installed.

### Troubleshooting

If testing was unsuccessful, review the following:

1. Sezzle Shift4Shop extension is the most updated version
2. Sezzle payment method is enabled
3. [API Keys](https://dashboard.sezzle.com/merchant/settings/apikeys) were entered correctly

   <Tip>
     It is recommended to use the Copy icon in the [Sezzle Merchant Dashboard](https://dashboard.sezzle.com/merchant/settings/apikeys) to avoid typos or extra spaces
   </Tip>
4. If you have multiple accounts with Sezzle, the merchant ID and API Keys are tied to only one URL
5. Sezzle on-site messaging widget script is present on your website and reflects the Merchant ID from your [Sezzle Merchant Dashboard](https://dashboard.sezzle.com/merchant/settings/business)
   1. Go to a product page on your website
   2. Right-click then select `Inspect`
   3. In the `Elements` tab, search for `widget.sezzle`

### Manual Theme Integration

If the Shift4Shop app fails to maintain the widget script on the product pages, or to add the script manually for additional pages, complete the following steps:

1. From your Shift4Shop admin, go to `Settings` > `Design` > `Themes & Styles`
2. In your Current Theme, click the button labeled `More` then select `Edit Template (HTML)`
3. Find the copy of your theme under `Go to Folder`
4. Click the gear icon next to the `product_items.html` file, then click `Edit`
5. When the dashboard asks if you want to edit your theme files, click the `Edit Theme Files` button
6. In the Source Code text area, copy and paste the script at the very beginning of the file
7. Click `Save`

### Insert Script into Webpage

Template:

```
<script src="https://widget.sezzle.com/v1/javascript/price-widget?uuid={sezzle_merchant_uuid}"></script>
```

<Note>
  Update `{sezzle_merchant_uuid}` in the above script template to reflect your site’s Merchant ID (removing the curly brackets), which can be found in the [Sezzle Merchant Dashboard](https://dashboard.sezzle.com/merchant/settings/business).
</Note>

Example:

```
<script src="https://widget.sezzle.com/v1/javascript/price-widget?uuid=12a34bc5-6de7-890f-g123-4hi5678jk901"></script>
```

<Tip>
  * Instructions may vary slightly depending on your active plug-ins.
  * For assistance with widget configuration, click `Request Addition of Widgets` in the widget step of your [Sezzle Merchant Dashboard Setup Checklist](https://dashboard.sezzle.com/merchant/checklist).
</Tip>

### Uninstall Steps

1. Go to `Settings` > `Payment`
2. Click `Select Payment Methods`
3. Under the Sezzle App, click the gear icon then click `Delete`