South Carolina Income Tax 2026

South Carolina has a graduated income tax for 2026. The standard deduction is $15,000 (single) / $30,000 (married filing jointly). Major 2026 reform: H.4216 (Act 110), signed March 30, 2026, effective tax year 2026 (returns due April 15, 2027), replaced the old 3-bracket system (top 6.0%/6.2%) with a two-rate structure on TAXABLE income: 1.99% on income up to $30,000 and 5.21% above $30,000 (computed as 5.21% of income minus $966 to credit the lower-bracket benefit). Brackets are the SAME for Single and MFJ - NOT doubled for joint filers. The deduction shown is the new SC Income-Adjusted Deduction (SCIAD), which decouples SC from federal deductions and uses federal AGI as the starting point: $15,000 Single/MFS, $22,500 Head of Household, $30,000 MFJ/surviving spouse. SCIAD phases out as income rises - Single reduced by a fraction (numerator = federal AGI over $40,000, denominator $55,000), reaching $0 above the range top (Single $40,000-$95,000; HoH $60,000-$142,500; MFJ $80,000-$190,000). No local/city income taxes in SC. Social Security benefits fully exempt. Taxpayers 65+ may deduct up to $10,000 retirement income plus a $15,000 age-65 deduction (reduced by retirement deduction claimed). Future automatic rate cuts: from TY2027, if BEA projects individual income tax revenue growth >=5% (cap: cut cannot reduce revenue by more than $200M), the top rate steps down toward 1.99% and eventually toward full elimination; BEA sets new rate by Feb 15 each year. Note: Tax Foundation's published 2026 table predates the late-March 2026 enactment and still showed pre-H.4216 brackets (0%/3%/6%, std ded $8,350/$16,700); SC DOR H.4216 guidance is authoritative for TY2026.