Credits to a customer's account can be made in the form of either a payment or credit memo.
The account balance will decrease by the amount of any credit applied to it. A credit’s balance can be allocated to one or more debit transactions (invoices or debit memos).
Adding Credit Memos
A credit memo can be added to a Customer's account by selecting to "Add Credit Memo" on the customer's page.
The amount to credit the account and a text description for the account adjustment must be provided to create the credit memo. Additionally, any allocations to existing invoices and debit memos on the customer's account can be specified here.
Once saved, the amount credited to the customer's account cannot be changed. If an amount is incorrectly entered or a credit added in error, a corresponding debit memo will need to be created to adjust the customer's balance. The credit memo can then be updated to allocate the relevant amount to this debit memo, bringing the debit balance to zero.
Payments can be applied to an account either through the admin "Add Payment" form on the customer's account page or, if configured, through your website's customer invoice page.
Adding a payment through the admin interface
From this page, you can enter the amount of the payment and provide allocations of the payment to individual invoices and debit memos. If allocating an entire invoice or debit memo's balance, that debit transaction will be closed.
A payment can be adjusted later to remove/add allocations.
Adding a payment through your website