If I amend my return, and TurboTax shows I am due a refund, but the State of California then calculates that I owe, will TurboTax cover the difference plus the penalty?

If you mail your State amendment today and send a check, there will be no penalty on a 2018 return.

Thanks. For the second part of the question, TurboTax calculated that I was owed an additional refund on my California amended return in March 2019. I mailed that in. When I logged in again a few weeks later in April 2019, TurboTax is now showing I actually owe the FTB if I amend my return again. There has been no change in my documentation. Will TurboTax cover the difference?

In other words, it appears TurboTax made a mistake in their calculation, showing I was owed a State refund, which I filed , assuming that the calculations were correct. Then later, after changing nothing in the TurboTax forms or adding no new documentation, TurboTax changed its calculations to show I owe. The difference is about $1,000. Which one is correct, the first one or the changed one?

I appreciate you responding. The question I have is whether or not TurboTax is liable to pay any penalty. The specific question I have is regarding the certified amended return they provided, which shows a refund amount. I filed that amended return. If it is denied by the California FTB because of an error, then how do I have TurboTax pay the penalty and tax owed as a result of their mistake?

See the answer to your other post: https://ttlc.intuit.com/community/after-you-file/discussion/turbotax-amended-return-error/00/816494