An arrangement between a financial institution, usually a bank, and a customer that establishes a maximum loan balance that the bank will permit the borrower to maintain, subject to special conditions, either secured or unsecured. The borrower can draw down on the credit line, subject to special conditions, as long as he or she does not exceed the maximum set in the agreement.

The advantage of a line of credit over a regular loan is that interest is not usually charged on the part of the line of credit that is unused, and the borrower can draw on the credit line at any time that he or she needs to. Depending on the agreement with the financial institution, the credit line may be classified as a demand loan, which means that any outstanding balance will have to be paid immediately at the financial institution's request.