Shift4Shop
Shift4Shop
This guide describes how to integrate Sezzle into your Shift4Shop website so that you can provide Sezzle as a payment option for your customers. After integrating Sezzle, your Shift4Shop site will:
- offer Sezzle as a payment option on the checkout page.
- refund Sezzle payments from your Shift4Shop order management system.
- display Sezzle promotional messaging.
- authorize and capture payments.
Integration Steps Overview
Before You Begin
- You should have a Sezzle merchant account.
- Please visit our signup page (US/CA) or signup page (EU) if you don't have an account.
- Make sure you have the following Sezzle details handy.
US/US
EU
- Familiarize yourself with the transaction flow when buying with Sezzle.
Install the Sezzle Shift4Shop Extension
- Log in to your website's Shift4Shop admin.
- Get the app here.
- Copy+paste your
Store URL
into the input area, then clickProceed
.


- Check the PCI Compliance box, then click
Acknowledge and Authorize the App
to start the installation.
Admin Configuration
- In your Shift4Shop admin, go to
Settings
>Payment
. - Click
Select Payment Methods
.


- Turn the Sezzle switch to
On
. - Copy your
Public Key
from your Sezzle Merchant Dashboard (US/CA) or Sezzle Merchant Dashboard (EU), and paste it into the corresponding field in the Sezzle configuration page of your Shift4Shop admin. - Next to
Private Key
, clickChange
. Then, copy yourPrivate Key
from your Sezzle Merchant Dashboard (US/CA) or Sezzle Merchant Dashboard (EU), and paste it into the corresponding field in the Sezzle configuration page of your Shift4Shop admin. - Click
Save
.


- To restrict Sezzle usage by country, click the
Exclude List
hyperlink under the Sezzle switch. - Click
Add Location
. - Select the desired country, then click
Add
.


- Installation is complete.
Shift4Shop Sandbox Testing
- In the Sezzle configuration page of your Shift4Shop admin, enter the Sandbox API Keys from your Sezzle Merchant Dashboard (US/CA) or Sezzle Merchant Dashboard (EU) and check the
Test Mode
checkbox, then save the configuration. Make sure you are doing this on yourdev
/staging
website. - On your website, add an item to the cart, then proceed to checkout and select
Sezzle
as the payment method. - Click
Place Order
and you should be redirected to the Sezzle checkout page. If prompted, sign in.


- Enter the payment details using test data then click
Complete Order
. - After the payment is completed on Sezzle, you should be redirected back to your website and see a successful payment page.
- Sandbox testing is complete. You can log in to your Sezzle Merchant Sandbox Dashboard (US/CA) or Sezzle Merchant Sandbox Dashboard (EU) to see the test order you just placed.
Shift4Shop Live Checkout
- In the Sezzle configuration page of your Shift4Shop admin, enter the API Keys from your Sezzle Merchant Dashboard (US/CA) or Sezzle Merchant Dashboard (EU) and uncheck the
Test Mode
checkbox, then save the configuration. - On your website, add an item to your cart, then proceed to
Checkout
and selectSezzle
as the payment method. - Click
Place Order
.


- If you are redirected to the Sezzle checkout page, your integration is complete. Congratulations!
- Warning Don't complete the payment. Your checkout is now live, so you will be charged if you complete.
Troubleshooting
If testing was unsuccessful, review the following:
- Sezzle Shift4Shop extension is the most updated version.
- Sezzle payment method is enabled.
- API Keys were entered correctly.
- It is recommended to use the Copy icon in the Sezzle Merchant Dashboard to avoid typos or extra spaces.
- If you have multiple accounts with Sezzle, the merchant ID and API Keys are tied to only one URL.
- Widget script is present on your website and reflects the
Merchant ID
from your Sezzle Merchant Dashboard (US/CA) or Sezzle Merchant Dashboard (EU). - Go to a product page on your website.
- Right-click then select
Inspect
. - In the
Elements
tab, search forwidget.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:
- From your Shift4Shop admin, go to
Settings
>Design
>Themes & Styles
. - In your
Current Theme
, click the button labeledMore
then selectEdit Template(HTML)
. - Find the copy of your theme under
Go to Folder
. - Click the
gear
icon next to theproduct_items.html
file, then clickEdit
. - When the dashboard asks if you want to edit your theme files, click the
Edit Theme Files
button. - In the
Source Code
text area, copy+paste the script at the very beginning of the file. - Click
Save
.
The script to be inserted into your webpage is as follows:
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.
Example:
<script src="https://widget.sezzle.com/v1/javascript/price-widget?uuid=12a34bc5-6de7-890f-g123-4hi5678jk901"></script>
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.
Uninstall Steps
- Go to
Settings
>Payment
. - Click
Select Payment Methods
. - Under the Sezzle App, click the
gear
icon then clickDelete
.
Updated 4 months ago