You can repay the principal at your convenience, but each month you must make the minimum payment set out in your monthly statement. This payment includes interest, insurance premiums (if applicable) and any additional amounts required to ensure your account balance does not exceed your credit limit. The minimum payment must be made without using the line of credit. The interest on a line of credit is calculated daily, as of the first day it is used. That's why it's a good idea to start repaying the balance as soon as possible. You can reuse the credit you've already repaid when you need it.
For more information on how a line of credit works, check out our page Compare financing solutions.