I have just migrated from Kashflow and have opening balances on customer invoices that have been paid before we migrated, how can I mark the invoices as paid

Hi info-simmonsbilt Thanks for reaching out to us here on the Community. We presume that after migrating the open balances for your customers within QuickBooks are showing as open invoices. If you would like to receive payments for those invoices but not allocate them to your bank accounts you could select the receive payment and allocate the payment to the undeposited funds account. The undeposited funds account is a nominal/chart of account so receiving payment to this account will affect the balance of the account however when you then then wish to allocate the payment to the bank account you can either change the account on the payment or create a bank deposit from the +New option > ensure your bank account is selected in the account field > select the relevant invoice > save and close. I have included an article that references allocating funds to the undeposited funds account and creating bank deposits: https://intuit.me/3Sz1lij