When an invoice is raised to a third-party and includes charges for a single client you can split the balance between the client and the third-party. This means that payments can be recorded on the client account and the third party account against the same invoice.
To split-bill an invoice open it up either from the client/third-party log or accounts screen. At the bottom you'll find a Split Billing option.
If this does not appear then ensure the invoice is raised to a third party. You can use the Change Invoicee option to alter this if it is not.
The split billing screen allows you to specify how much of the invoice the client should pay and how much the third-party should pay.
If the invoice has been part paid already then this will be reflected here.
From here you need to enter the client's name and the third party name in the description and then click in the “To Pay” column and enter the amount you want your client to pay. Once you’ve changed the “To Pay” cost in the client row it will automatically adjust the total in the Third-Party row when you click out of the box. Once you're happy with the distribution of the balance click the OK button.
You will now notice that in red letters it states that the invoice has been split and it will show you the values of the split. Accordingly it will show you below how much of the invoice has been paid by both separate sides.
When coming to pay the invoice that has been split, in the second option it shows you the balances due from both parties. In the 3rd section it will record the payment from either your client or 3rd party in the normal way. The only difference being, you now have 2 payment columns, of which the left hand side is for client payments, the right hand side for third-party payments.