STATE GUIDE · UPDATED 2026
Every OurPrenup agreement is built for the laws where you live.
Start your South Dakota prenupYes — prenuptial agreements are legally enforceable in South Dakota under the Uniform Premarital Agreement Act (UPAA) (SDCL §§ 25-2-16 to 25-2-25). To be valid, the agreement must be in writing, signed voluntarily by both partners, and made with fair financial disclosure. It should be notarized (strongly recommended, though not legally required), and both partners should have a real opportunity to review it well before the wedding.
Courts divide marital property fairly (not necessarily equally) unless your agreement says otherwise.
Yes. South Dakota enforces prenuptial agreements under the Uniform Premarital Agreement Act (UPAA). The governing law is SDCL §§ 25-2-16 to 25-2-25. The agreement must be in writing and signed by both partners, entered into voluntarily, and made with fair financial disclosure.
Notarization is not strictly required in South Dakota, but strongly recommended — a notarized agreement is significantly harder to challenge in court, and OurPrenup's South Dakota signing instructions include it.
No — South Dakota does not require witnesses for a prenuptial agreement. Both partners' signatures (ideally notarized) are what matter.
No — South Dakota does not require either partner to hire a lawyer for a valid prenup. Independent review is still recommended, and every OurPrenup agreement documents that both partners had the opportunity to seek counsel.
No. South Dakota is an equitable distribution state — without an agreement, courts divide marital property "fairly," which is not necessarily equally. A prenup replaces that uncertainty with rules you both chose.
No. South Dakota does not allow prenuptial agreements to modify or waive spousal support — South Dakota deliberately omitted UPAA § 3(a)(4) when adopting the UPAA in 1989 (SL 1989, ch 216, § 3). Connolly v. Connolly (270 N.W.2d 44, S.D. 1978) invalidated an alimony waiver. Sanford v. Sanford (2005 SD 34) reaffirmed post-UPAA: the legislature intentionally omitted spousal-support waiver authority. Spousal support waivers are void as against public policy. OurPrenup automatically leaves support to state law in South Dakota agreements.
Each partner must make a fair and reasonable disclosure of their assets, debts, and income before signing. Hiding assets is the fastest way to make a prenup unenforceable in South Dakota. OurPrenup builds sworn financial disclosure schedules for both partners into every agreement.
South Dakota has no fixed statutory deadline, but signing well before the wedding matters: agreements signed days before a wedding are the easiest to attack as pressured. Most attorneys recommend having the agreement finished at least 30 days before the wedding.
Attorney-drafted prenups in South Dakota commonly run $1,500–$5,000+ per couple. OurPrenup is a flat $599 per couple for a complete South Dakota-specific prenuptial agreement, financial disclosure schedules for both partners, a plain-language summary, and step-by-step South Dakota signing instructions — with optional online e-sign and notarization for $50.
Both parties review the final prenuptial agreement and all attached financial schedules.
Both parties sign the prenuptial agreement.
Have the agreement notarized. While South Dakota does not legally require notarization, we strongly recommend it. Notarized agreements are significantly harder to challenge in court.
Keep the original signed agreement in a safe location. Provide copies to both parties and their attorneys.
3 people total at signing
This guide is general information about South Dakota law, not legal advice. For advice on your specific situation, consult a licensed attorney in South Dakota. See our full legal disclaimer.
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