2.3 Tax Compliance: Payroll, Sales/Use & State Requirements

Tax Compliance: Payroll, Sales/Use & State Requirements

Tax compliance in commercial construction encompasses federal payroll withholdings, federal and state unemployment taxes, state corporate/individual income taxes, and specialized state sales and use taxes. Failure to withhold, remit, or pay mandatory taxes exposes general contractors to catastrophic monetary penalties, personal liability under statutory "responsible person" provisions, mechanics' liens from taxing authorities, and immediate revocation of the contractor's South Carolina General Contractor license under Title 40, Chapter 11.

1. Federal Payroll Taxes & Mandatory Withholdings

General contractors with direct employees (superintendents, project managers, carpenters, laborers) must comply with federal payroll tax statutes enforced by the Internal Revenue Service (IRS).

FICA: Social Security & Medicare

The Federal Insurance Contributions Act (FICA) establishes mandatory funding for federal Social Security and Medicare programs. FICA is a shared liability between the employer and the employee:

1. Social Security Tax (OASDI):

   • Employee Rate: 6.2% withheld from employee gross wages.
   • Employer Match: 6.2% contributed directly by the employer (totaling 12.4%).
   • Wage Base Cap: Applies only up to the statutory annual wage base limit set annually by the Social Security Administration ($184,500 for 2026, up from $176,100 in 2025; indexed annually). Any employee earnings exceeding this threshold are exempt from further Social Security withholdings for the remainder of the calendar year.

2. Medicare Tax (Hospital Insurance):

   • Employee Rate: 1.45% withheld from employee gross wages.
   • Employer Match: 1.45% contributed directly by the employer (totaling 2.9%).
   • No Wage Base Limit: Medicare tax applies to 100% of all gross wages paid to an employee without any dollar limitation.

3. Additional Medicare Tax:

   • An additional 0.9% Medicare tax must be withheld from employee wages that exceed $200,000 in a calendar year ($250,000 for married couples filing jointly).
   • This 0.9% tax is paid solely by the employee; there is no employer matching contribution.

Federal Income Tax Withholding (FITW)

Employers must withhold federal personal income tax from each employee's paycheck based on:

• The employee's completed IRS Form W-4 (Employee's Withholding Certificate), which accounts for marital status, dependents, multiple jobs, and additional requested withholding amounts.
• IRS withholding tables (percentage method or wage-bracket method published in IRS Publication 15-T).
• Unlike FICA, FITW involves no employer matching contribution; the employer acts as a fiduciary collection agent for the federal government.

Trust Fund Recovery Penalty

FICA taxes and FITW withheld from employee paychecks are legally classified as Trust Fund Taxes. They belong to the federal government from the moment they are withheld. Under IRC § 6672, if a construction business fails to remit trust fund taxes, the IRS can assess a 100% Trust Fund Recovery Penalty personally against any "responsible person" (company officers, directors, managing members, or individuals with check-signing authority). This personal liability cannot be discharged in corporate or personal bankruptcy.

2. Federal & South Carolina Unemployment Taxes

Unemployment taxes fund joint federal-state unemployment compensation systems that provide temporary financial relief to workers who lose employment through no fault of their own.

Federal Unemployment Tax Act (FUTA)

FUTA is an employer-paid tax. It cannot be withheld or deducted from employee wages.

• Taxable Wage Base: FUTA applies only to the first $7,000 of taxable wages paid to each employee in a calendar year.
• Statutory Gross Rate: The gross FUTA tax rate is 6.0%.
• State Unemployment Credit (FUTA Tax Credit):
  • Employers that pay their state unemployment taxes (SUTA) fully and on time receive a maximum credit of up to 5.4% against the gross FUTA rate.
  • This reduces the effective net FUTA tax rate to 0.6% (6.0% - 5.4% = 0.6%).
• Effective Annual Cost: For an employee earning $7,000 or more annually: $$\text{Net Annual FUTA} = \$7,000 \times 0.006 = \$42.00 \text{ per employee}$$
• Credit Reduction Warning: If a state borrows funds from the federal unemployment trust fund (Title XII advances) to pay state benefits and fails to repay them within statutory deadlines, the federal government reduces the 5.4% credit for employers in that state, resulting in higher federal FUTA tax bills.

South Carolina State Unemployment Tax (SUTA / SCDEW)

South Carolina unemployment insurance is administered by the South Carolina Department of Employment and Workforce (SCDEW) pursuant to the South Carolina Employment Security Law (S.C. Code Ann. Title 41).

• Employer-Paid: Like FUTA, SUTA is paid strictly by the employer; zero deductions may be taken from worker paychecks.
• Taxable Wage Base: The South Carolina taxable wage base is established by statute (e.g., $14,000 per employee per year).
• Experience Rating System: SCDEW assigns annual tax rates to employers based on an experience rating / benefit ratio system:
  • An employer's tax rate is calculated by comparing unemployment benefits paid out to former employees against the total taxable wages reported and taxes paid by the employer over the preceding three years.
  • Employers with frequent layoffs and high turnover incur higher contribution rate brackets.
  • Employers with stable payrolls, minimal turnover, and strong reserve account balances qualify for the lowest statutory tax rate classes.
• New Employer Rate: A newly formed commercial construction company in South Carolina with no prior wage or benefit history is assigned a statutory entry rate for its first 12 to 24 months of operation until it builds an independent experience history with SCDEW.

3. South Carolina Department of Revenue (SCDOR) Requirements

Contractors operating within South Carolina must register with the South Carolina Department of Revenue (SCDOR) via MyDORWAY and comply with state-specific business and income tax requirements.

South Carolina State Income Tax Withholding

Employers operating in South Carolina must withhold South Carolina individual income tax from all wages paid to employees for services performed within the state.

• Withholdings are calculated based on the employee's state withholding allowances (Form SC W-4) and state withholding tax tables.
• Depending on the total monthly withholding volume, taxes must be deposited quarterly, monthly, or on an accelerated schedule matching federal deposit rules.
• The employer submits quarterly withholding reconciliations (Form WH-1605) and an annual state reconciliation (Form WH-1606).

Non-Resident Contractor Withholding

Under S.C. Code Ann. § 12-8-550, a person who hires a nonresident for temporary business or personal services in South Carolina must withhold 2% of each payment when the South Carolina portion of the contract exceeds, or could reasonably be expected to exceed, $10,000. No withholding is required if the nonresident has registered with the Secretary of State or SCDOR and so submitted to South Carolina tax jurisdiction. A contractor that obtains the nonresident's affidavit of registration is not responsible for withholding.

4. South Carolina Sales and Use Tax in Construction

Understanding the mechanics of South Carolina Sales and Use Tax (S.C. Code Ann. Title 12, Chapter 36) is one of the most heavily tested legal domains on the South Carolina Business Management & Law examination.

The Fundamental Legal Principle: Contractors as Consumers

In many states, contractors are treated as retailers who purchase materials tax-free and resell them to property owners. In South Carolina, the legal rule is precisely the opposite:

Core South Carolina Rule: For tax purposes, a construction contractor who constructs, alters, repairs, or improves real property is legally deemed to be the CONSUMER of all tangible personal property (building materials, structural elements, fixtures, supplies) purchased for use in the performance of the construction contract.

Practical Application of the Contractor-as-Consumer Rule

1. Sales Tax Paid at Point of Purchase: When a general contractor or subcontractor purchases lumber, concrete, structural steel, rebar, drywall, mechanical ductwork, or electrical conduit from a South Carolina building supply vendor, the contractor must pay the 6% state sales tax plus applicable local option sales taxes (which range from 1% to 3% depending on the county and municipality) directly to the vendor at the time of purchase.
2. Resale Certificates Prohibited: A contractor cannot present a South Carolina Resale Certificate (Form ST-8A) to a supplier to buy materials tax-free for a real property construction contract, because the materials are not being resold as tangible personal property—they are being converted into real property improvements.
3. No Sales Tax on Customer Invoices: Because the contractor has already paid sales tax as the consumer, the contractor does not charge sales tax as a separate line item on customer progress billings (e.g., AIA G702). The contractor includes the paid sales tax as part of the direct material cost built into the contract sum or bid estimate.
4. Labor Exemption: Pure installation and construction labor performed on real property is not subject to South Carolina sales tax, provided that charges for labor are not bundled into a taxable retail sale of untransformed personal property.

South Carolina Use Tax

When a contractor purchases construction materials from a vendor located outside South Carolina, the transaction triggers Use Tax liability:

• Trigger: Occurs when materials, tools, or equipment are purchased out-of-state (e.g., from a manufacturer in Ohio or Georgia) where no sales tax, or a sales tax rate lower than South Carolina’s rate, was charged, and the materials are subsequently brought, shipped, or delivered into South Carolina for use on a construction project.
• Tax Rate: The Use Tax rate is identical to the Sales Tax rate: 6% state rate plus applicable local option taxes.
• Reporting & Payment: If the out-of-state vendor does not collect South Carolina tax, the general contractor has the legal duty to self-assess, report, and pay the Use Tax directly to SCDOR on the state sales and use tax return (Form ST-3).
• Credit for Taxes Paid Elsewhere: If another state legally collected a sales tax on the material, South Carolina grants a credit up to the amount paid, but if the other state's tax was less than the applicable South Carolina rate, the contractor must pay the differential to SCDOR.

5. Federal Tax Reporting Forms & Regulatory Schedule

To maintain tax standing, contractors must strictly adhere to federal and state reporting calendars:

Subcontractor 1099-NEC Compliance & Backup Withholding

A major compliance area for commercial contractors is the proper engagement of trade trade subcontractors:

• Mandatory Reporting: Contractors must file Form 1099-NEC for each unincorporated independent contractor, sole proprietor, or single-member LLC paid $2,000 or more for services during the year. That threshold applies to payments made after December 31, 2025, and will be indexed for inflation beginning in 2027. Payments made in 2025 and earlier used the old $600 threshold, so older study materials still show $600.
• Mandatory Form W-9: Prior to issuing the first progress payment to any trade subcontractor, the general contractor must require a signed Form W-9 certifying the subcontractor's correct legal name and Taxpayer Identification Number (TIN) or Employer Identification Number (EIN).
• Backup Withholding (24%): If a subcontractor refuses or fails to provide a valid TIN/EIN on Form W-9, the general contractor is federally mandated under IRC § 3406 to withhold 24% backup withholding from all disbursements made to that subcontractor and remit those funds directly to the IRS. If the contractor fails to withhold, the contractor becomes personally liable for the uncollected tax.