SC2210: Underpayment of Estimated Tax by Individuals, Estates, and Trusts (2025)

Who files this form

SC2210 helps individuals, estates, and trusts determine whether they paid enough South Carolina Income Tax during 2025 and whether they owe an underpayment penalty. If your SC1040 or SC1041 Income Tax liability is $100 or more, you must prepay through withholding or estimated tax payments. That does not automatically mean you must file SC2210.

Complete Part I, lines 1 through 6 first. If line 3 or line 6 is less than $100, you do not owe a penalty and should not file SC2210.

Part II lists these reasons for filing:

• Box A: You request a waiver of the entire penalty.
• Box B: You request a waiver of part of the penalty.
• Box C: Your income varied during the year, and the Annualized Income Installment Method reduces or eliminates your penalty.
• Box D: Your penalty is lower when wage withholding is treated as paid on the actual withholding dates.
• Box E: You filed jointly for 2024 or 2025, but not both years, and Part I, line 7 is less than line 4.

If box B, C, or D applies, calculate your penalty and file SC2210. If only box A or E applies, file only pages 1 and 2; you do not have to calculate the penalty. If no Part II box applies, the form generally tells you not to file SC2210. Separate attachment instructions apply to qualifying farmers and fishermen.

When it's due

For tax year 2025, SC2210 lists these estimated tax payment due dates:

• April 15, 2025
• June 15, 2025
• September 15, 2025
• January 15, 2026

If you file your 2025 return and pay the tax due by January 31, 2026, there is no penalty for the January 15, 2026 installment. Underpayment periods for earlier installments end on January 15, 2026, but earlier penalties are not erased.

For the farmer and fisherman exception for tax year 2025, the instructions require filing SC1040 and paying the entire tax by March 1 following the end of the tax year. If March 1 falls on a weekend, the deadline is the next business day.

What you'll need

Have these returns and payment details available:

• Your 2025 SC1040 or SC1041. Part I uses tax after credits from SC1040, line 15 or SC1041, line 13, refundable credits from SC1040, lines 21 and 22, and withholding from SC1040, lines 16, 19, and 20.
• Your 2024 tax information for Part I, line 7, including adjusted gross income information used to determine whether the 110% rule applies.
• Amounts and dates of estimated tax payments and withholding used to calculate any underpayment.

Depending on your situation, you may also need:

• Federal Schedule AI completed for South Carolina purposes if using the Annualized Income Installment Method.
• A statement explaining the waiver request if requesting a partial penalty waiver under box B.
• Federal Form 2210F completed for South Carolina purposes if you meet the farming and fishing income test but not the filing-and-payment condition.

Individual taxpayers must provide their Social Security Number on SC2210.

How to file

Complete Part I, then check every applicable box in Part II to determine what to submit.

• If box B, C, or D applies, calculate your penalty and file SC2210.
• If box A or E applies, but B, C, and D do not, submit only pages 1 and 2. The department will calculate any penalty and bill you for an unpaid amount.
• If you calculate a penalty, enter the line 26 total on SC1040, line 33 or SC1041, line 19, subject to the waiver instructions.

For the annualized method, write Annualized to the left of SC2210, line 9. Write For South Carolina Purposes at the top of federal Schedule AI, attach it to your return, and enter exception code A on SC1040, line 33.

For a waiver, check box A or B and attach SC2210 to your Income Tax return. For box B, complete through line 25, enter the requested waiver amount in parentheses to the left of line 26, and enter the penalty remaining after the requested waiver on line 26. Include a statement explaining the request. Enter exception code W on SC1040, line 33.

The supplied text does not provide a mailing address or e-file instructions.

Common mistakes

• Including estimated or extension payments as withholding on line 5. The form specifically says not to include them there.
• Filing SC2210 when a stop instruction applies. If Part I, line 3 or line 6 is less than $100, stop and do not file the form.
• Completing Part III across rows instead of by column. Complete lines 11 through 17 of one column before moving to the next. Follow the same column-by-column approach for lines 18 through 25.
• Assuming a later payment cancels earlier penalties. Paying the 2025 estimated liability by January 15, 2026, or filing and paying by January 31, 2026, does not erase penalties for earlier underpayments.
• Submitting page 3 when only pages 1 and 2 are required. If only box A or E applies, Part III may be used as a worksheet, but the form says to file only pages 1 and 2.

Questions people ask

Can I owe a penalty even if I do not have to file SC2210?

Yes. If no Part II box applies, the form says not to file SC2210. The department will calculate the penalty and send a bill for any unpaid amount.

What exceptions can eliminate the penalty?

The instructions say no penalty applies if your prior-year tax liability was $0 for a full 12 months, or if the total tax on your 2025 return minus withholding is less than $100.

Can uneven income during the year reduce my penalty?

Yes. The Annualized Income Installment Method may lower your required installments. Complete federal Schedule AI for South Carolina purposes and follow the box C instructions.

When can I request a penalty waiver?

All or part of a penalty may be waived for an underpayment caused by a casualty, disaster, or other unusual circumstance when imposing the penalty would be inequitable. A waiver may also apply if you retired after age 62 or became disabled in 2024 or 2025 and the underpayment had reasonable cause, or if the penalty is attributable to personal service income earned in another state where that state's Income Tax was withheld.

Is there a special rule for farmers and fishermen?

Yes. No penalty applies if farming and fishing provided at least two-thirds (66.67%) of your gross income for 2024 or 2025 and you meet the filing-and-payment deadline described above. Enter F in the exception box on SC1040, line 33 and attach SC2210. If you meet the income test but not the filing-and-payment condition, complete federal Form 2210F for South Carolina purposes, label it For South Carolina Purposes, and attach it to your Income Tax return.

Official sources

• https://dor.sc.gov/sites/dor/files/forms/SC2210_2025.pdf