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

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Install the Sezzle Payments App

  1. Log in to your website’s Shopify admin

  2. Install the Sezzle Payments app

    1. Go to Settings > Payments
    2. Under Supported Payment Methods, click Add Payment Method
    3. Search for Sezzle
    4. Click the result in the dropdown, then click Sezzle Payments
    5. Click Manage Account
    6. Click Install

  3. Enter your production Sezzle public and private API keys

    • For most merchants, we are able to pre-fill the public and private API keys based on the Shopify store
    • If we cannot uniquely identify the merchant based on the Shopify store, you will be required to fill in the keys

  4. Click Save to verify your Sezzle account

    • You will be redirected to the payment settings page, where you will need to activate Sezzle Payments for your store

  5. Click Activate

  6. Verify Sezzle is available as a payment method for your store

You should see Sezzle Payments installed in your Settings > Payments

Without activating Sezzle Payments, Sezzle will not appear in the checkout, and the installation process is not complete. Verify this step has been completed.

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Validate

For Sandbox testing, do this step first

  1. Navigate to Settings > Payments > Sezzle Payments
  2. Click Manage, check Enable test mode, and click Save
  3. Click the Manage button in Sezzle Payments, enter your sandbox API keys in the test tab
  4. Click Update settings

For Live testing, do this step first

  1. In the Sezzle configuration page of your Shopify admin, enter the API keys from your Sezzle Merchant Dashboard
  2. Uncheck the Enable Test Mode checkbox
  3. Save the configuration

Step through a test checkout to validate the integration is properly installed.

The Shopify “Accepted Payment Methods” footer widget does not support third-party payment apps by default. To show Sezzle in this section, follow the instructions provided by Shopify, adding 'sezzle' to the list.

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Troubleshooting

If testing was unsuccessful, review the following:

Sezzle Payments Shopify extension is the most updated version

  • Go to Apps > Sezzle Payments, then click About
  • If there is an option to upgrade, do so now

Sezzle gateway is activated

  • Go to Settings > Payment Providers and ensure “Sezzle is active” is listed under the Alternative Payment Methods section

API keys were entered correctly

  • 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

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Uninstall the Sezzle Payments App

  1. Go to Apps

  2. Find Sezzle Payments and click Delete

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FAQs