Because most companies closely monitor cash flow, it helps to offer an incentive to encourage early payment. The longer outstanding invoices sit on the books, the more it costs the company.
1234, Main Street
Boston, MA 02123
<Recipient Address Goes Here>
Enclosed is our invoice for <what invoice is for>. We want to remind you about our early payment discount. If we receive payment <time deadline>, we will discount the total amount due by <amount of discount>. <Other restrictions.>.
We hope you are able to take advantage of this discount. We look forward to serving you in the future.
encl: <List of enclosed items goes here>