If a $100 check is entered as received from a customer in QuickBooks Online, which account is debited?

When a $100 check is entered as received from a customer in QuickBooks Online, the Cash Account is debited because you are increasing your cash balance with the money coming in from the customer. In accounting, debiting the cash account reflects the increase in cash assets that the business has received.

This process begins with the customer paying their outstanding invoice, which decreases the Accounts Receivable account if the payment relates to a billed item. However, since the question specifically focuses on what happens when the check is recorded in QuickBooks Online, the focus is on the immediate cash impact. Debiting the Cash Account recognizes the transaction's effect on liquidity, as the business is gaining cash in hand.

While the Accounts Receivable account would also be involved in the background if this check was for a previously invoiced service, the primary transaction recorded immediately is the increase in Cash, which is why the Cash Account is the correct answer.