When is the earliest I can file my return in 2018?

[MichaelDC]

The latest from TurboTax regarding Forms Availability: 

“We apologize that the forms are not available right now. They will be updated tonight. Please check back tomorrow (1/19/18) for the updated forms.”

Most forms should be available by end of day January 18. However, the IRS will begin accepting e-file returns on January 29, 2018. (A few returns will be processed up to a week before this date for testing purposes.)

If you file your return in TurboTax before January 29, we'll hold your return and submit it at that time.

Note: If your return is among those that the IRS processes early as part of its testing, your tax refund (if any) won't be processed until after January 29.