Yes, the Magento 2 Store Credit Extension supports partial payments. Customers can choose to pay for their order partially with Store Credit and use another payment method for the remaining amount if needed.

Read this How to Configure Store Credit Extension in Magento 2 Store to setup this extension.

Here are the few more resource to help you get most out of this Magento 2 Store Credit Extension.

• Maximizing revenue with Magento 2 Store Credit Extension
• Raise Loyalty & Returning Visitors with Magento 2 Store Credit Extension
• Store Credit in eCommerce: A Key to Customer Retention