South Carolina Quarterly Tax Calculator
Calculate your estimated quarterly tax payments for federal and South Carolina state taxes. Designed for self-employed individuals, freelancers, and independent contractors.
SC State Tax: Progressive 0.0% - 6.4%
Quarterly Payment Amount
$6,609
Per quarter (4 remaining)
Annual Tax Breakdown
2026 Payment Schedule
Jan 1 - Mar 31
Due: April 15, 2026
$6,609
Apr 1 - May 31
Due: June 15, 2026
$6,609
Jun 1 - Aug 31
Due: September 15, 2026
$6,609
Sep 1 - Dec 31
Due: January 15, 2027
$6,609
Don't miss your quarterly payments!
The IRS may charge penalties and interest if you underpay or pay late. Consider setting up automatic payments or calendar reminders.
South Carolina Quarterly Tax Highlights
South Carolina has 3 brackets: 0%, 3%, and 6.4%
First $3,460 is tax-free
Being phased to a flat tax
South Carolina Quarterly Tax FAQ
What is South Carolina's income tax rate?
South Carolina has a progressive income tax: 0% on first $3,460, 3% on income from $3,460 to $17,330, and 6.4% on income above that. The state is transitioning to a flat tax system.
South Carolina Estimated Quarterly Tax Payments for Self-Employed Workers in 2026
Self-employed workers in South Carolina must pay both federal estimated taxes to the IRS and state estimated taxes to the South Carolina Department of Revenue. South Carolina has a progressive income tax with 3 brackets and rates ranging from 0% to 6.4%. If you expect to owe $100 or more in South Carolina state income tax after withholding and credits, you must make quarterly estimated payments using Form SC1040ES.
South Carolina exempts the first $3,460 of income from tax. The state is in the process of transitioning to a flat tax rate. South Carolina requires estimated payments if you expect to owe $100 or more in state tax after credits.
| Tax Layer | Rate / Range | Filed With | Form |
|---|---|---|---|
| Federal income tax | 10% – 37% | IRS | 1040-ES |
| Self-employment tax | 15.3% | IRS | 1040-ES / SE |
| South Carolina state income tax | 0% to 6.4% | South Carolina Department of Revenue | Form SC1040ES |
How South Carolina Income Tax Affects Your Quarterly Payments
South Carolina taxes personal income — including self-employment income — across 3 progressive brackets. The brackets below apply to single filers for tax year 2026. Married filing jointly thresholds are typically higher.
| Bracket | Taxable Income | Marginal Rate |
|---|---|---|
| 1 | $0 – $3,460 | 0% |
| 2 | $3,460 – $17,330 | 3.0% |
| 3 | $17,330+ | 6.4% |
To estimate your South Carolina quarterly payment, calculate your projected state tax liability using the brackets above, then divide by four. South Carolina payments are made to the South Carolina Department of Revenue through their online portal at dor.sc.gov or by mail using Form SC1040ES.
Federal Self-Employment Tax and Quarterly Due Dates
All self-employed workers must pay federal self-employment (SE) tax of 15.3% on 92.35% of net earnings. This consists of 12.4% for Social Security (on earnings up to $184,500 in 2026) and 2.9% for Medicare (no cap). An additional 0.9% Medicare surtax applies to earnings above $200,000 (single filers).
Both South Carolina and federal estimated tax payments follow the same quarterly schedule:
| Quarter | Income Period | Due Date |
|---|---|---|
| Q1 | January 1 – March 31 | April 15, 2026 |
| Q2 | April 1 – May 31 | June 15, 2026 |
| Q3 | June 1 – August 31 | September 15, 2026 |
| Q4 | September 1 – December 31 | January 15, 2027 |
To avoid underpayment penalties, pay at least 100% of your prior-year tax liability (or 110% if your AGI exceeds $150,000) spread across four equal payments, or at least 90% of your current-year tax. You can deduct 50% of your self-employment tax from your adjusted gross income, reducing both your federal and South Carolina taxable income.
Related Calculators
Official References
This calculator uses current federal and South Carolina tax rates and schedules:
- IRS Estimated Tax Guidelines
Federal quarterly tax requirements and Form 1040-ES
- SC DOR
Official South Carolina tax authority
- IRS Self-Employment Tax
Social Security and Medicare tax information
This calculator provides estimates based on 2026 tax rates. Your actual tax liability may vary based on deductions, credits, and other factors. Consult a tax professional for personalized advice.