South Carolina Remote Employee Tax Withholding: Progressive Rates and Rate Cuts

South Carolina has steadily reduced its individual income tax rates over the past several years, with the top rate dropping from 7.0% before 2022 to 6.3% for 2025 under a multi-year reform package enacted in 2022. The state has no reciprocity agreements with neighboring North Carolina or Georgia, which makes cross-border commuting and remote-work arrangements more compliance-intensive than in states with extensive reciprocity networks. This guide walks through the South Carolina tax landscape, residency rules, withholding for residents and non-residents, the absence of reciprocity, SUI mechanics, out-of-state employer obligations, the resident credit for taxes paid to other states, South Carolina-specific wage laws, recent developments, and common payroll mistakes.

South Carolina's Tax Landscape

South Carolina levies a progressive individual income tax with a top marginal rate of 6.3% for 2025, down from 6.4% in 2024 and 7.0% before 2022, under the reform legislation enacted as Act 231 of 2022. The 2025 rate schedule taxes the first $3,460 of taxable income at 0%, income from $3,461 to $17,330 at 3%, and income above $17,330 at 6.3% for single filers, with bracket thresholds approximately doubled for married filing jointly. South Carolina uses the federal standard deduction, which is $14,600 for single filers and $29,200 for married filing jointly for 2025. The South Carolina Department of Revenue (SC DOR) administers the state income tax and publishes annual withholding tables in its employer tax guide.

South Carolina also offers significant retirement-income exclusions that affect withholding calculations for retired employees. Residents age 65 or older can exclude up to $15,000 of retirement income from qualified retirement plans, and Social Security retirement benefits are fully exempt from South Carolina income tax. Residents under 65 can exclude up to $3,000 of qualified retirement income. These exclusions, combined with the state's moderate top rate and the federal standard deduction, give South Carolina a relatively competitive tax burden compared to neighboring North Carolina (flat 4.25%) and Georgia (flat 5.39%), although the top rate remains higher than both.

South Carolina Residency Rules

South Carolina residency is determined under two tests: domicile and statutory residency. Domicile is the place where an individual has their true, fixed, and permanent home and to which they intend to return whenever absent. The SC DOR applies a multi-factor domicile test that examines the individual's location of family, business activities, time spent in South Carolina versus elsewhere, location of real and tangible personal property, and persistence of South Carolina ties such as voter registration, driver's license, vehicle registration, and bank accounts. South Carolina residents are taxed on all income regardless of source, while non-residents are taxed only on South Carolina-source income.

South Carolina statutory residency applies when an individual maintains a permanent place of abode in South Carolina and spends more than 183 days of the tax year inside the state. A statutory resident is taxed as a resident on all income, even if their domicile is in another state. The 183-day rule is strictly enforced by the SC DOR, which operates an active residency audit program targeting individuals who claimed to have moved out of South Carolina, particularly to Florida and other no-income-tax states. Taxpayers who maintain a South Carolina residence while claiming domicile elsewhere should keep detailed day-count logs and contemporaneous records of their physical presence.

Withholding for South Carolina Residents

South Carolina residents are subject to South Carolina income tax on all income regardless of source, and employers must withhold South Carolina income tax from wages paid to South Carolina residents. The withholding calculation uses Form SC W-4, the South Carolina Employee's Withholding Allowance Certificate, which is separate from the federal Form W-4. The SC W-4 collects information about the employee's expected allowances, additional voluntary withholding, and exemption claims. Employees who claim exemption from South Carolina withholding must check the appropriate box on Form SC W-4 and renew the exemption annually by February 15.

The South Carolina withholding formula applies the progressive rate schedule to projected annual wages after subtracting the federal standard deduction (allocated per pay period) and any allowances claimed on Form SC W-4. The SC DOR publishes annual withholding tables in the employer tax guide that simplify the per-pay-period calculation. Employers should use the current year's tables and update payroll systems each January. Supplemental wages, such as bonuses and commissions, are subject to South Carolina supplemental withholding at 6.3% (the top rate) with no allowance adjustment.

Withholding for Non-Residents

South Carolina non-residents are subject to South Carolina income tax only on South Carolina-source income. For employees, South Carolina-source income means wages earned while physically performing services in South Carolina. A non-resident employee who works entirely outside South Carolina for a South Carolina employer has no South Carolina-source wages and no South Carolina withholding obligation. Non-resident withholding is computed by allocating the employee's annual wages across states based on the days worked in each state, then applying South Carolina withholding to the South Carolina-allocated portion.

South Carolina does not enforce a convenience rule for non-resident employees of South Carolina employers who work remotely outside South Carolina. This means that a North Carolina resident who works remotely from their North Carolina home for a South Carolina employer has no South Carolina withholding obligation, provided the work is performed entirely outside South Carolina. However, the same North Carolina resident who commutes into South Carolina for occasional in-person meetings should track those days carefully, because days physically worked in South Carolina create South Carolina-source wages and a corresponding withholding obligation. The non-resident employee files Form SC1040NR to reconcile South Carolina tax at year-end.

South Carolina Reciprocity (None)

South Carolina does not have income tax reciprocity agreements with any state, including neighboring North Carolina and Georgia. This is a significant compliance burden for multi-state commuters and remote workers in the border regions. A North Carolina resident who commutes to South Carolina for work is subject to South Carolina income tax on the wages earned in South Carolina, and North Carolina taxes the resident on all wages with a credit for taxes paid to South Carolina on the North Carolina resident return. A Georgia resident in the same situation faces similar dual-filing obligations.

An employee who expects to owe no South Carolina tax because they are a resident of another state and perform no work in South Carolina cannot claim exemption from South Carolina withholding via a reciprocity form, because no reciprocity agreement exists. The only way to stop South Carolina withholding is for the employee to perform no South Carolina-source work and for the employer to allocate wages accordingly. The lack of reciprocity is a frequent source of confusion for payroll teams, particularly those transferring employees between North Carolina and South Carolina offices.

SUI (South Carolina Department of Employment and Workforce)

South Carolina State Unemployment Insurance is administered by the South Carolina Department of Employment and Workforce (SC DEW) under the South Carolina Employment Security Law. The new employer SUI rate is approximately 1.0% for most non-construction industries, with a higher rate for new construction employers. The SUI wage base is $14,000 per employee per year for 2025, producing a maximum new-employer per-employee contribution of $140 (1.0% × $14,000) for non-construction. After the initial period (typically the first two to three years), the rate becomes experience-rated based on the employer's benefit charge ratio and taxable payroll.

Experience-rated South Carolina SUI rates range from 0.06% to 5.46% under the standard tax schedule, with a separate schedule applying during periods of state trust-fund insolvency. South Carolina also imposes a 0.06% contingency assessment on the taxable wage base to fund administrative costs and a 0.10% surcharge for the South Carolina workforce development program, which funds reemployment services and training programs. Employers file quarterly Form UCE-120 wage reports with SC DEW and remit contributions by the standard quarterly deadlines (April 30, July 31, October 31, and January 31). Failure to file timely can trigger FUTA credit reductions and additional penalties.

Out-of-State Employer With a South Carolina Remote Employee

An out-of-state employer that hires a South Carolina remote employee creates South Carolina payroll tax nexus and must register with the South Carolina Department of Revenue for an income tax withholding account and with the South Carolina Department of Employment and Workforce for an SUI account. The two registrations are separate and produce separate account numbers. The income tax withholding registration is completed online through the SC DOR MyDORWAY portal, and the SUI registration is completed through the SC DEW SUITS online system. Both registrations typically process within five to ten business days.

Once registered, the out-of-state employer must withhold South Carolina income tax from the remote employee's wages using the SC W-4 and the SC DOR withholding tables, file quarterly Form WH-1601 withholding returns, and file annual Form WH-1606 reconciliation with W-2 copies by January 31. The employer must also file quarterly Form UCE-120 wage reports with SC DEW and remit SUI contributions on the first $14,000 of wages per South Carolina employee per year. Foreign-entity registration with the South Carolina Secretary of State may also be required for corporations and LLCs transacting business in South Carolina. Workers' compensation coverage must be in place for the South Carolina employee under South Carolina Workers' Compensation Law.

South Carolina Resident Working for an Out-of-State Employer

A South Carolina resident who works remotely for an out-of-state employer is still subject to South Carolina income tax on all wages, regardless of where the employer is located. South Carolina taxes its residents on worldwide income. The out-of-state employer should register with the SC DOR and withhold South Carolina income tax from the resident employee's wages, although many out-of-state employers fail to do this initially and the resident must make estimated tax payments to cover the South Carolina liability. If the work state also taxes the resident (because the work state does not have reciprocity with South Carolina and sources wages to the employer's state), South Carolina provides a credit for taxes paid to other states.

The credit for taxes paid to other states is claimed on Form SC1040TC and is attached to the South Carolina resident return Form SC1040. The credit is nonrefundable and is capped at the South Carolina tax attributable to the same out-of-state income, calculated by multiplying the total South Carolina tax by the ratio of out-of-state income to total income. South Carolina does not enforce a convenience rule, so a South Carolina resident who works remotely for a New York or Connecticut employer is not exposed to the convenience-rule trap. However, if the resident occasionally works in the employer's state, that state may source a portion of the wages to itself, creating a creditable tax liability that the resident claims against South Carolina tax.

South Carolina-Specific Wage Laws

South Carolina follows the federal minimum wage of $7.25 per hour, as the state has not enacted a higher minimum wage. The South Carolina Payment of Wages Act, codified in the South Carolina Code of Laws Title 41, Chapter 10, governs the timing and method of wage payment for South Carolina employees. Wages must be paid on regular paydays designated in advance, with no statutory minimum frequency, although the SC DOL's practical guidance is that employees should be paid at least semimonthly. Final paychecks for terminated employees must be delivered within 48 hours of separation or by the next regular payday, whichever is later.

Accrued unused vacation is not required to be paid out at separation unless the employer's policy or contract provides for it, which is more lenient than states like Illinois and Pennsylvania. South Carolina is an at-will employment state and a Right to Work state, meaning union-security agreements requiring union membership as a condition of employment are prohibited. South Carolina's workforce development programs, administered through SC DEW and the state's regional workforce boards, provide hiring incentives and training grants for employers that create new jobs in the state. The South Carolina Workforce Investment Act coordinates federal WIOA funding for training programs targeting in-demand industries.

Recent South Carolina Tax Developments

The most significant recent South Carolina tax development is the continued implementation of the Act 231 of 2022 income tax reform, which collapsed the prior six-bracket progressive structure (with a top rate of 7.0%) into a three-bracket structure with a top rate that began declining in 2023. The top rate fell to 6.4% for 2024 and 6.3% for 2025, and further cuts are scheduled through 2026 contingent on revenue triggers being met. The reform also collapsed the prior bracket structure by capping the top rate at 6.5% (later 6.3%) and reducing the number of brackets from six to three. The SC DOR has updated its withholding tables annually to reflect the new rates.

The reform legislation also included a provision that reduces the top rate by 0.1 percentage points each year that state general fund revenue growth exceeds a specified threshold, with a long-term statutory target of 6.0%. The SC DOR confirmed in 2024 that the revenue triggers were met for the 2024 and 2025 rate reductions, and the rate reduction schedule is on track for the 2026 reduction. Employers should monitor SC DOR announcements each fall to confirm the rate for the upcoming tax year and update payroll systems in January.

Common South Carolina Payroll Mistakes

The most common South Carolina payroll mistake is using the wrong year's tax rate. The Act 231 rate reduction schedule means that the South Carolina top rate changes annually, and using the prior year's rate produces systematic under- or over-withholding. Employers must update their payroll systems each January to apply the current year's rate as published by the SC DOR. The second common mistake is failing to register for both the SC DOR withholding account and the SC DEW SUI account, which are separate registrations that produce separate account numbers.

The third common mistake is mishandling the lack of reciprocity. South Carolina does not have reciprocity with any neighboring state, and employers often incorrectly assume that residents of North Carolina or Georgia who work in South Carolina are exempt from South Carolina withholding via a reciprocity form. The fourth common mistake is failing to file Form WH-1601 quarterly withholding returns even in zero-wage quarters, which generates penalties. The fifth common mistake is mishandling supplemental wages, which are subject to South Carolina supplemental withholding at the top rate of 6.3% with no allowance adjustment. The sixth common mistake is failing to file Form WH-1606 annual reconciliation with W-2 copies by the January 31 deadline. The seventh common mistake is mishandling the credit for taxes paid to other states on Form SC1040TC for residents working in neighboring states. The eighth common mistake is failing to track day-count for non-resident employees who occasionally work in South Carolina, which creates South Carolina-source wages that require withholding.

What to Do Next

Audit your South Carolina payroll compliance using the eight common mistakes above. Verify that your SC DOR withholding account and SC DEW SUI account are both active and that quarterly Form WH-1601 and Form UCE-120 returns are filed on time, including zero returns for no-wage quarters. Confirm that SUI contributions stop at the current $14,000 wage base per employee and that the new employer rate is correctly applied in your payroll system. Update your payroll system to apply the 2025 top rate of 6.3% (down from 6.4% in 2024), and monitor SC DOR announcements in the fall to confirm the 2026 rate. Verify that Form SC W-4 is on file for every South Carolina employee and that the workforce development surcharge is included in your SUI remittance. If you have a South Carolina resident working for an out-of-state employer, confirm that the credit for taxes paid to other states is being claimed on Form SC1040TC. Run our multi-state withholding calculator for each South Carolina employee to verify the full federal and state payroll picture.