If your business invoices customers, you have likely faced cash flow challenges due to slow (or non) payment. Slow-paying customers are frustrating because they hinder your ability to meet expectations, replenish inventory and pay your team. Send all outstanding invoices as well as an account statement with the phrase "ACCOUNT PAST DUE" prominently displayed on the statement. Inform the manager that the customer's account is on hold and no further work can be performed. Related: How to Talk to Customers in Default the Right WayConsiderations on litigationWhile litigation is sometimes inevitable, it is best to avoid suing non-paying customers.