You can downgrade using the Clear and Start Over feature but bear in mind that the different TurboTax "flavors" handle different tax situations and their associated forms.
Keep in mind that TurboTax Free Edition is intended for taxpayers with very simple returns (Form 1040EZ filers with the standard deduction), like first-time filers and students.
"Free Edition is for simple filers that file a 1040EZ (or a 1040A with a standard deduction), and is free as long as you don't select any add-ons or upgrades."
Please review the following TurboTax FAQ on how to review and remove unwanted fees:
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