It depends.  I don't recommend immediately paying separately for the reason you state above.  If the return was slow in processing (accepted almost on the day of payment processing, for example), it can take a few extra business days to be taken from the account.  In addition, you may wish to double-check the bank information from which the payment should be withdrawn to make sure that information is correct.  If in doubt, however, you would do well to contact the KY Department of Revenue to see the status of your return and your payment.  They can give you other payment options if there was an issue with withdrawing the payment on time.  For information on how to contact them, please click on the following website link: