Interest on unpaid invoices in South Carolina: 8.75% a year if no rate was agreed; the most you can set depends on the deal

South Carolina's rate when no rate was agreed

8.75% a year. 8.75% a year on accounts stated and sums ascertained and due.

• “In all cases of accounts stated and in all cases wherein any sum or sums of money shall be ascertained and, being due, shall draw interest according to law, the legal interest shall be at the rate of eight and three-fourths percent per annum.” — S.C. Code § 34-31-20(A), read November 6, 2026
• “The legal rate of interest is equal to the prime rate as listed in the first edition of the Wall Street Journal published for each calendar year for which the damages are awarded, plus four percentage points, compounded annually.” — S.C. Code § 34-31-20(B), read November 6, 2026

The most you can set in South Carolina

For a homeowner: Consumer credit sale: 18% a year, or a higher rate the creditor has filed and posted under S.C. Code § 37-2-305. Applies to a 'consumer credit sale' — goods or services bought by an individual for personal, family or household use from a seller who regularly extends that kind of credit, payable in installments or with a credit service charge.

For a business customer: No cap by agreement for a sale other than a consumer credit sale. § 37-2-605: for a sale other than a consumer credit sale (e.g. to an organization or for business purposes), the parties may contract for any credit service charge.

• “The credit service charge, calculated according to the actuarial method, may not exceed the greater of either of the following: (a) any rate filed and posted pursuant to Section 37-2-305, or (b) eighteen (18%) percent per year on the unpaid balances of the amount financed.” — S.C. Code § 37-2-201(2), read November 6, 2026
• “Every creditor (Section 37-1-301(13)), intending to impose a credit service charge in excess of eighteen percent per annum other than an assignee of a credit obligation, making consumer credit sales (Section 37-2-104) in this State” — S.C. Code § 37-2-305, read November 6, 2026
• “"consumer credit sale" is a sale of goods, services, or an interest in land in which: (a) credit is granted by a person who regularly engages as a seller in credit transactions of the same kind; (b) the buyer is a person other than an organization; (c) the goods, services, or interest in land are purchased primarily for a personal, family or household purpose; (d) either the debt is payable in installments or a credit service charge is made;” — S.C. Code § 37-2-104(1), read November 6, 2026
• “With respect to a sale other than a consumer credit sale, the parties may contract for the payment by the buyer of any credit service charge.” — S.C. Code § 37-2-605, read November 6, 2026

Late fees in South Carolina

What the text says: For a consumer credit sale, the parties may contract for a delinquency charge on any installment not paid in full within ten days after its due date (S.C. Code § 37-2-203(1)). Consumer credit sales (goods or services to an individual for personal, family or household use), including seller credit cards. The statute's base figure is $5, adjusted every even-numbered July 1 by the Dept. of Consumer Affairs.

• “With respect to a consumer credit sale including an open-end consumer credit sale pursuant to a seller credit card, and any refinancings or consolidations of all such credit sales, the parties may contract for a delinquency charge on any installment not paid in full within ten days after its due date, as originally scheduled or as deferred, in an amount not exceeding five dollars, which is not more than five percent of the unpaid amount of the installment.” — S.C. Code § 37-2-203(1), read November 6, 2026
• “Notwithstanding subsection (1) the seller may contract for and receive a minimum delinquency charge not to exceed forty percent of five dollars as adjusted pursuant to Section 37-1-109.” — S.C. Code § 37-2-203(2), read November 6, 2026
• “2.203(1) Delinquency Charge – Sales 23.00 25.50 2.203(2) Minimum Delinquency Charge 9.20 10.20” — S.C. Dept. of Consumer Affairs, Changes in Dollar Amounts, S.C. State Register Vol. 48, Issue 3 (Mar. 22, 2024) (S.C. Code § 37-1-109), read November 6, 2026
• “Pursuant to Section 37-1-109, designated dollar amounts in the Consumer Protection Code are subject to change on July 1 of every even-numbered year based on the Consumer Price Index for Urban Wage Earners and Clerical Workers (CPI-W).” — S.C. Dept. of Consumer Affairs, Dollar Amount Adjustment (S.C. Code § 37-1-109), read November 6, 2026

Does South Carolina want it agreed in advance?

Agreed in advance: yes, in the cases below. The delinquency charge is one 'the parties may contract for' (§ 37-2-203(1)).

• “With respect to a consumer credit sale including an open-end consumer credit sale pursuant to a seller credit card, and any refinancings or consolidations of all such credit sales, the parties may contract for a delinquency charge on any installment not paid in full within ten days after its due date, as originally scheduled or as deferred, in an amount not exceeding five dollars, which is not more than five percent of the unpaid amount of the installment.” — S.C. Code § 37-2-203(1), read November 6, 2026

Homeowners and businesses in South Carolina

South Carolina's own words on it are below.

• “"consumer credit sale" is a sale of goods, services, or an interest in land in which: (a) credit is granted by a person who regularly engages as a seller in credit transactions of the same kind; (b) the buyer is a person other than an organization; (c) the goods, services, or interest in land are purchased primarily for a personal, family or household purpose; (d) either the debt is payable in installments or a credit service charge is made;” — S.C. Code § 37-2-104(1), read November 6, 2026
• “With respect to a sale other than a consumer credit sale, the parties may contract for the payment by the buyer of any credit service charge.” — S.C. Code § 37-2-605, read November 6, 2026

Prompt payment on private construction in South Carolina

What the text says: 1% a month from the due date when payment to a contractor is more than 21 days late, or to a subcontractor more than 7 days after the contractor/subcontractor is paid. Private construction financed by a nonowner (lender), excluding residential homebuilders and residential projects of 16 or fewer units. Does not apply to residential homebuilders, residential projects of 16 or fewer units, or private owners whose improvements are not financed by a nonowner.

• “If a periodic or final payment to a contractor is delayed by more than twenty-one days or if a periodic or final payment to a subcontractor is delayed by more than seven days after receipt of periodic or final payment by the contractor or subcontractor, the owner, contractor, or subcontractor shall pay his contractor or subcontractor interest, beginning on the due date, at the rate of one percent a month or a pro rata fraction thereof on the unpaid balance as may be due.” — S.C. Code § 29-6-50, read November 6, 2026
• “The provisions of this chapter do not apply to: (1) residential homebuilders; (2) improvements to real property intended for residential purposes which consist of sixteen or fewer residential units; or (3) private persons or entities owning improvements to real property when the specific improvements are not financed by a nonowner.” — S.C. Code § 29-6-60, read November 6, 2026

Work out a late charge in South Carolina

Starts at South Carolina's 8.75%, the rate when none was agreed, not a maximum.

What was not checked for South Carolina

• South Carolina's adjusted late-charge figure from July 1, 2026 was not found; the Department of Consumer Affairs page linked only the 2024 notice, good through June 30, 2026.

Check South Carolina's own text

Before you charge: read S.C. Code § 34-31-20(A) and the other South Carolina texts quoted on this page, or ask a lawyer. As of November 6, 2026.

This is a plain-words summary of each state's own laws as of November 6, 2026, not legal advice. Rules have exceptions. Check the state's own text, linked on every state's page, or a lawyer before you charge a late fee or interest.

Compare South Carolina with every state's answer, or with its neighbours just below.

Next door to South Carolina

• Georgia: 7% if none agreed, depends by agreement (not fully confirmed)
• North Carolina: 8% if none agreed, depends by agreement

Official sources for South Carolina

• S.C. Code § 34-31-20(A) — read November 6, 2026
• S.C. Code § 37-2-201(2) — read November 6, 2026
• S.C. Code § 37-2-605 — read November 6, 2026
• S.C. Dept. of Consumer Affairs, Changes in Dollar Amounts, S.C. State Register Vol. 48, Issue 3 (Mar. 22, 2024) (S.C. Code § 37-1-109) — read November 6, 2026
• S.C. Dept. of Consumer Affairs, Dollar Amount Adjustment (S.C. Code § 37-1-109) — read November 6, 2026
• S.C. Code § 29-6-50 — read November 6, 2026

Every state in one file: Excel and CSV downloads

Where our data comes from