With TurboTax Online, the fee for the state is for using TurboTax to prepare your state tax return. The fee is the same whether you e-file or file by mail. There is no additional fee for e-filing.
It may depend on which version of TurboTax you purchased.
With TurboTax Deluxe, there is no charge to fill out a single state, it is included in the purchase price. E-filing the Federal form is free, no extra cost. It does cost extra to e-file the state, $25. There is no extra cost if you mail your state form.