If you are referring to the TurboTax online editions for tax year 2024, you can pay the TurboTax account fees at any time before filing the tax return.
To pay the TurboTax online account fees by credit card, without completing the 2024 return at this time, click on Tax Tools on the left side of the online program screen. Then click on Print Center. Then click on Print, save or preview this year's return. On the next page, to pay by credit card, click Pay Now. The next screen will show a review of your Fees. Complete the credit card section and click on Confirm payment.