Worksheet for credit shows $33,333 on Step 3, item 6 but maximum should be $30,000. I believe this is the source of the error.
The information on your return is most likely correct.
According to "INCREASE IN TWO WAGE EARNER CREDIT" on page 3 of 2018 SC1040 INDIVIDUAL INCOME TAX FORM AND INSTRUCTIONS,
The maximum credit available for the Two Wage Earner Credit (claimed by a married couple filing jointly when both taxpayers have earned income taxed to South Carolina) has increased. For 2018, the credit is computed at 0.7% of the lesser of $33,333 or the SC qualified earned income of the taxpayer with the lower qualified income for the taxable year.
Same thing happening again this year for 2019! My printed return shows a Credit of $257 and on the return it says "Do Not Enter More Than $233)!
I agree that the regulations say the maximum credit is $233, and I don't know why TurboTax provides a different number.
If you file your return as it is stated the state will correct the entry if it is wrong, however. And TurboTax guarantees the accuracy of their calculations, so if there were any penalties or interest assessed because the amount was wrong, TurboTax would refund them to you.
However, due to the size of discrepancy here, that would be unlikely.
The maximum for 2017 was $210 (0.7% of $30,000), but the cap is increasing gradually until it reaches $350 (0.7% of $50,000) for 2023. So the max credit for tax year 2020 will be $280, for 2021 it will be $303, and for 2022 it will be $327. The calculation is right, the worksheet is wrong,
https://law.justia.com/codes/south-carolina/2018/title-12/chapter-6/section-12-6-3330/