To pay your TaxAct Online product fees at any time:
From within your TaxAct return (Online), click the My Return dropdown, then click My Return Details.
Scroll down to the Payment Information section, then click My Return Fees.
On the screen titled My TaxAct Return Fees, click Pay Now (if you have a pop-up blocker, your browser might block the window; change your browser settings to see the pop-up).