Sign into your Netflix account.
Click "Your Account and Help." Click the "Change Plan" option in the "Account Information" section.
Select the new plan you would like to have.
Click the "Continue" button at the bottom of the page. The applicable charges for upgrading will appear. Your charge for the current month is prorated and appears next to "Charge for Current Month." Your new monthly charge, which will start on your next billing date, appears next to "Charge for Next Month."
Click "Confirm Change." A banner stating that you have successfully changed your plan will appear, and your credit card on file will be charged accordingly.