Can I upgrade to Premiere after having already purchased Deluxe? How much more will it cost for 2018 taxes?

[Critter]

If you prepaid for the downloaded Deluxe version then you have no need to upgrade since all the downloaded versions have all the same tax forms and abilities.  The only difference is the amount of extra help in the interview questions.  So you can start with the Deluxe and upgrade in program if you feel the need and just pay the difference at that time ... right now the difference is $30.