You can make an online payment to your Gap Visa card at Gap's official website. The Credit Card link at the top of the home page and the Gap Card links at the bottom take you to the store's credit card homepage.
At the store's credit card home page, you can register your card's online account. You must fill in your account number and personal details, including an email address, billing address, user ID and password, according to Gap.com. You also need to choose from various options, such as receiving your bill online.
Once you have registered your account, return to the Gap.com credit card website, and enter your user ID and password in the login box. This action directs you to your online account page, which contains your past and current billing statements, rewards, and other account information. Near your account summary is a link that allows you to make a payment.
To add a debit card or bank account to pay your Gap Card balance, you must enter account details. After you have completed that, you can enter an amount you want to pay towards your account balance. After clicking submit, it may take several days for the payment to post to your account, so the site advises you to pay at least three to five days ahead of the due date for your statement.