With an equity line of credit you only pay interest on the amount of money that you are borrowing. (starloanservices.com)
Choose the frequency and amounts you want to draw on the loan, and you'll only be charged interest on the amount of money used from the line of credit. (reversemortgages.com)
And, you only pay interest on the amount of credit you use — not any of the available line you don't use. (ondeck.com)