Do I need to pay South Carolina State income tax quarterly

[ericahaislip]

I am self-employed and currently pay the IRS quarterly taxes, but am unsure if I am supposed to pay the state of South Carolina quarterly for state taxes.  

[ScruffyCurmudgeon]

It would appear that South Carolina also expects "pay as you earn" Estimated Taxes:

Form SC1040ES

• https://dor.sc.gov/forms-site/Forms/SC1040ES_09302015.pdf   Worksheet for computing Estimated Tax in SC
  
  
• https://dor.sc.gov/services-site/Documents/ePay%20IIT%20Dec%20User%20Guide.pdf#search=estimated  Electronic payment of SC Estimated Tax

[Anonymous]

What is the penalty for paying by April 15 rather than paying the estimated taxes?  If there is a penalty, is it better to do the Form 2210 or let the state compute?

[MaryK4]

The penalty is computed quarterly and it is 4% so you take the amount due for the quarter and divide it by the number of days in the quarter and multiply it by the 4%- it is six of one or half dozen of the other- either way will be straight math. 

@Anonymous

[Anonymous]

I am surprised by the division by the number of days.  Let's say the amount underpaid for the quarter is $1800.  Then take 90 days in the quarter.  Divide and that is $20.  Then I multiply by 4% to get the penalty?  Seems small.

[MaryK4]

Yes, the underpayment penalties are small but enough to get people's attention- and they can add up if you do have all year requirements.  

@Anonymous