§ StatuteRates

South Dakota Prejudgment Interest Rate

United States  South Dakota prejudgment interest — a formula rate, reset periodically.

Current rate
10% per year — current formula value, effective July 9, 2026
Set by statute Formula rate

South Dakota prejudgment interest is currently 10% per year — a statutory formula rate under SDCL 21-1-13.1 that resets periodically. Broad availability but with sharp claim-type carve-outs.

When South Dakota prejudgment interest applies

Broad availability but with sharp claim-type carve-outs. Any person entitled to recover damages (principal action, counterclaim, cross-claim, or third-party claim) is entitled to prejudgment interest. IMPORTANT: South Dakota does NOT limit prejudgment interest to liquidated or readily ascertainable sums — after the 1990 amendment, SDCL 21-1-13.1 allows prejudgment interest on unliquidated damages as well, with the accrual mechanism (verdict-specified date) handling uncertain loss dates.

When it starts accruing

Interest accrues from the day the loss or damage occurred, except during any period the debtor is prevented by law, or by act of the creditor, from paying the debt.

Simple or compound

Simple. The statute (SDCL 21-1-13.1 / 54-3-16) does not authorize compounding, and South Dakota courts apply simple interest for prejudgment interest.

How the rate is set

Fixed statutory value. Default = Category B rate under SDCL 54-3-16 = 10% per year. Exception: contract claims take the contract's stated rate if the contract provides one (otherwise 10%).

→ Compare with the South Dakota post-judgment interest rate (interest after judgment)

Prejudgment interest under SDCL 21-1-13.1 — 10% (simple interest). This is PREjudgment interest (accruing before entry of judgment) and is separate from South Dakota’s post-judgment rate; availability is limited by claim type (see the page). Current formula value as of 2026-07-09; verify at sdlegislature.gov. Not legal advice.

Effective-date history

1 data point on record. Full history in the JSON API.
Effective dateRateBasis
July 9, 2026 10% Statute

Source & provenance

Latest value retrieved July 10, 2026 (02:55 UTC) from the official source:
https://sdlegislature.gov/Statutes/21-1-13.1

Reference data only — not legal, tax, or financial advice. Always confirm the controlling value against the official source and, where applicable, the governing statute or court before relying on it.