When you use Salonized Pay, you receive an invoice every month for the transaction costs of Salonized Pay, giving you more insight into your accounting. This invoice is for information purposes only; an extra payment is not necessary as the costs have already been settled with the payout of your Salonized Pay transactions.
This invoice, like your other Salonized invoices, can be found at Settings > Billing and you receive it by email. This will be around the first day of the month and contains an overview of the transaction costs of the previous month.
This is what the invoice looks like: