SlimPay is a Direct Debit payment gateway supporting both BACS Direct Debit for UK based customers and SEPA for EU based customers.
What is Direct Debit?
Direct Debit is a pull-based bank-to-bank payment method: a customer authorises a merchant to automatically debit their bank account of the amount of the subscription.
The first time a user pays an invoice using the SlimPay payment gateway, they will be asked to complete a mandate that authorizes you (the merchant) to debit their bank account automatically each subscription cycle. The customer only has to do this once.
Upon creation of a mandate for the first time, a payment request will be initiated. Until such time as the payment has fully completed, the invoice will display a "Payment Pending" status and display a message to the user as shown below. No automated provisioning actions will be performed until the payment has fully cleared, unless you enable the Instant Activation for New Orders option.
For recurring invoices where a mandate agreement already exists between you and the customer, WHMCS will automatically request a payment capture on the due date of the invoice.
SlimPay supports payments in Euro and British Pounds. The module will automatically select the appropriate BACS or SEPA payment method based on the currency of the invoice.
Navigate to Setup > Payments > Payment Gateways. Select the All Payment Gateways tab. Now click the SlimPay button to activate it.
You will be prompted for your SlimPay App ID, Secret and Creditor Reference which should have been provided to you by SlimPay.
The Return URL inside your SlimPay account should be set to the following:
Instant Activation for New Orders
Direct debit is not an instant payment service. Payments can take up to a few days to clear and fully complete processing.
If you wish to provision new orders immediately upon the completion of a mandate agreement and initiating of a payment, to avoid the customer having to wait while the payment clears, you can check the "Instant Activation for New Orders" option in the SlimPay payment gateway settings and this will trigger the invoice to be marked paid and any successful payment automation actions to be carried out immediately.
The SEPA scheme allows an eight week period where a payment received can be rejected or reversed by the payee. WHMCS will monitor for any changes in the payment status of invoices paid via SlimPay during this time and will automatically process these as appropriate.
To learn more, visit Payment Reversals
SlimPay have a sandbox for testing the payment integration. You can apply for sandbox credentials here: https://dev.slimpay.com/hapi/login?signup