Final answer:
If a customer underpays an invoice, a business can either leave the amount as underpayment or write off the extra amount, which means they will not pursue the remaining debt.
Step-by-step explanation:
If a customer underpays an invoice, as a business, you have a couple of options regarding the remaining unpaid balance. You can either leave the amount as an underpayment on the account, or you may write off the extra amount. If you decide to write off the unpaid amount, you essentially forgive the remaining debt, which means you accept the loss and do not expect to receive that portion of the payment from the customer. This might be done for various reasons, such as maintaining a good customer relationship or if the amount is too small to justify the cost of collection. However, it's important to note that frequent write-offs can negatively affect the business's financial health.