The term INVOICES TO PAY can be broken down into two crossword solutions: BILLS (5 letters) and INVOICES (8 letters). BILLS is a term used to refer to an itemized statement of money owed for goods or services. An INVOICE is a document sent by a seller to a buyer, listing the goods or services provided and the amount due for payment. Together, INVOICES TO PAY refers to the process of paying for goods or services that have been purchased.