How do I file both state & federal for free?

[SamiaI]

There is  TurboTax® Absolute Zero offer,  where federal and state is for free.

TurboTax® Absolute Zero® offers over 60 million Americans the ability to file their federal 1040A or 1040EZ returns, as well as their state tax returns, for absolutely $0. After March 15, if you have a simple tax return, you can still file your federal tax return for free. Additional fees apply for state tax preparation.