Contest a Will in South Dakota - Best Proven Guide (2026)

By Oleg Kachko · Updated September 6, 2026

✓ Verified September 2026

To contest a will in South Dakota, you file in the probate court within a fixed window and prove one of a short list of legal grounds. This guide gives the South Dakota answer in plain English, and it starts with the deadline, because that is the fact that ends more cases than any other. All facts are from South Dakota law, verified as of September 2026.

In This South Dakota Guide:

At a Glance
The Deadline
The Grounds
Who Can Contest
No-Contest Clauses
The Steps
Settling
What to Expect
Official Sources

Contest a Will in South Dakota: At a Glance

Here are the South Dakota facts that decide whether you can contest a will in South Dakota:

Deadline to contest	To contest an INFORMALLY probated will, a formal testacy proceeding must be commenced within the later of 12 months from the date of the informal probate or 3 years from the decedent’s death (SDCL 29A-3-108). SDCL 29A-3-108 also imposes an absolute 3-year outer limit measured from the decedent’s death for commencing any informal probate, formal testacy, or appointment proceeding (with narrow statutory exceptions for a will previously probated at the testator’s domicile, an estate with a prior appointment, a prior proceeding dismissed for doubt about the fact of death, and absentee/conservatorship estates). Once a will is probated in a FORMAL testacy proceeding, the order is final as to all persons given notice; an interested person who did not oppose the will at the original hearing may petition to vacate and reopen under SDCL 29A-3-412, and appeal from a final probate order is governed by SDCL 15-26A (30 days from notice of entry of the order). The exact numeric vacation window inside SDCL 29A-3-412 could not be verified from an official South Dakota source in this research — UNVERIFIED for that sub-deadline.
What starts the clock	Two triggers run in parallel under SDCL 29A-3-108 and the contestant gets the LATER of them: (1) the date the will was admitted to informal probate by the clerk (12 months), and (2) the decedent’s date of death (3 years). Death is the trigger for the absolute 3-year bar. For a will already admitted in a formal testacy proceeding, the trigger is entry of the formal testacy order plus the notice given under SDCL 29A-3-403 (SDCL 29A-3-412).
Who can contest	Any “interested person” may petition (SDCL 29A-3-401, 29A-3-402, 29A-1-201). In South Dakota this includes heirs at law who would take by intestacy, devisees and beneficiaries under the will, children, spouses, beneficiaries under a prior or later will, creditors, and any other person having a property right in or claim against the estate — and also persons with priority for appointment as personal representative. Standing is measured by whether the person’s interest may be affected by the outcome, and it can change as the proceeding progresses.
No-contest clause	YES with a probable-cause exception. SDCL 29A-3-905 (“Penalty clause for contest”) provides that a provision in a will purporting to penalize an interested person for contesting the will or instituting other proceedings relating to the estate is UNENFORCEABLE if probable cause exists for instituting the proceedings. So the clause is valid and will be enforced against a contestant who had no probable cause, but it cannot forfeit the inheritance of a contestant who brought the challenge with probable cause. For trusts, the parallel and notably stricter provision is SDCL 55-1-46, which defines a no-contest clause and addresses its enforceability separately from the will rule.
What the filing is called	A “Petition for Formal Testacy Proceeding” (petition for formal probate of a will, or petition to set aside informal probate / to adjudicate intestacy), filed in the probate file in the circuit court under SDCL 29A-3-401 and 29A-3-402. Where a formal testacy order has already been entered, the filing is a petition to vacate the order and reopen the matter under SDCL 29A-3-412. Objections to a pending formal petition are filed as written objections under SDCL 29A-3-404. Filing must be in the county of proper venue, and under SDCL 29A-1-303 the county where a proceeding is first commenced has the exclusive right to proceed.
Court	The South Dakota circuit court. South Dakota has no separate probate or surrogate court — probate, formal testacy, and will contests are heard by the circuit court in the county of the decedent’s domicile at death (or, for a nonresident, the county where property is located), under SDCL 29A-1-301 and SDCL 29A-1-303. Uncontested informal probate is handled administratively by the clerk of courts acting as registrar; a contest moves the matter to the circuit judge.
Jury trial	YES. SDCL 29A-1-306 provides that if duly demanded, a party is entitled to trial by jury in a formal testacy proceeding and in any proceeding in which a controverted question of fact arises as to which a party has a constitutional right to trial by jury. Where there is no right to a jury, or the right is waived, the court may in its discretion call a jury, but that verdict is advisory only. The demand must be made timely under South Dakota’s civil procedure rules.
Typical cost	UNVERIFIED — South Dakota courts and the State Bar of South Dakota do not publish typical contested-will litigation cost figures. Costs vary widely with estate size, discovery, expert medical testimony, and whether a jury is demanded. Under SDCL 29A-3-720 a personal representative who defends or prosecutes a proceeding in good faith may be allowed necessary expenses and attorney fees from the estate. Ask a licensed South Dakota probate attorney for a fee estimate on your specific facts.

The Deadline to Contest a Will in South Dakota

⚠ Deadline to contest a will in South Dakota: To contest an INFORMALLY probated will, a formal testacy proceeding must be commenced within the later of 12 months from the date of the informal probate or 3 years from the decedent’s death (SDCL 29A-3-108). SDCL 29A-3-108 also imposes an absolute 3-year outer limit measured from the decedent’s death for commencing any informal probate, formal testacy, or appointment proceeding (with narrow statutory exceptions for a will previously probated at the testator’s domicile, an estate with a prior appointment, a prior proceeding dismissed for doubt about the fact of death, and absentee/conservatorship estates). Once a will is probated in a FORMAL testacy proceeding, the order is final as to all persons given notice; an interested person who did not oppose the will at the original hearing may petition to vacate and reopen under SDCL 29A-3-412, and appeal from a final probate order is governed by SDCL 15-26A (30 days from notice of entry of the order). The exact numeric vacation window inside SDCL 29A-3-412 could not be verified from an official South Dakota source in this research — UNVERIFIED for that sub-deadline.. The clock starts at Two triggers run in parallel under SDCL 29A-3-108 and the contestant gets the LATER of them: (1) the date the will was admitted to informal probate by the clerk (12 months), and (2) the decedent’s date of death (3 years). Death is the trigger for the absolute 3-year bar. For a will already admitted in a formal testacy proceeding, the trigger is entry of the formal testacy order plus the notice given under SDCL 29A-3-403 (SDCL 29A-3-412).. Missing it usually ends the case regardless of how strong the grounds are.

The window is short in some states and long in others, and it is measured from a specific event rather than from the day you learned about the will. That is why the first thing to find out is the date the will was admitted and whether you received formal notice. If the deadline has not run, everything else on this page is available to you.

If it has, the remaining options are narrow and usually involve proving you never got the notice the law required.

Grounds to Contest a Will in South Dakota

Lack of testamentary intent or lack of testamentary capacity; undue influence; fraud; duress; mistake; and revocation — these are the grounds expressly allocated to the contestant in SDCL 29A-3-407.

Improper execution / failure to meet the formalities of SDCL 29A-2-502 (signed by the testator, or by another in the testator’s conscious presence and at the testator’s direction, and signed by at least two witnesses) and forgery are separately available, though under SDCL 29A-3-407 the proponent carries the burden on due execution.

Who has to prove what: Split under SDCL 29A-3-407. The PROPONENT of the will has the burden of establishing prima facie proof of due execution in all cases, and of death, venue, and heirship if those are contested. The CONTESTANT then carries the burden of establishing lack of testamentary intent or capacity, undue influence, fraud, duress, mistake, or revocation. The standard is preponderance of the evidence.

South Dakota case law recognizes a rebuttable PRESUMPTION OF UNDUE INFLUENCE where a confidential relationship existed between the testator and a beneficiary who took an active part in preparing or procuring the will and unduly profited from it; when that presumption arises, the burden of going forward shifts to the beneficiary to show the will was the free act of the testator.

South Dakota’s classic four-element undue influence test requires: susceptibility of the testator, opportunity to exert influence, disposition to do so, and a result clearly showing the effect of that influence.

Who Can Contest a Will in South Dakota

Any “interested person” may petition (SDCL 29A-3-401, 29A-3-402, 29A-1-201). In South Dakota this includes heirs at law who would take by intestacy, devisees and beneficiaries under the will, children, spouses, beneficiaries under a prior or later will, creditors, and any other person having a property right in or claim against the estate — and also persons with priority for appointment as personal representative.

Standing is measured by whether the person’s interest may be affected by the outcome, and it can change as the proceeding progresses. Being unhappy with the will is not standing; losing something because of it is. Check the earlier will and the intestate rules for South Dakota before filing, because they decide whether you are an interested person.

No-Contest Clauses in South Dakota

YES with a probable-cause exception. SDCL 29A-3-905 (“Penalty clause for contest”) provides that a provision in a will purporting to penalize an interested person for contesting the will or instituting other proceedings relating to the estate is UNENFORCEABLE if probable cause exists for instituting the proceedings.

So the clause is valid and will be enforced against a contestant who had no probable cause, but it cannot forfeit the inheritance of a contestant who brought the challenge with probable cause. For trusts, the parallel and notably stricter provision is SDCL 55-1-46, which defines a no-contest clause and addresses its enforceability separately from the will rule.

The Steps to Contest a Will in South Dakota

Step one is the deadline check above. Step two is evidence: the medical records around the signing date, the names of the witnesses, the drafting lawyer’s file, and the financial records that show who benefited.

Step three is the filing — A “Petition for Formal Testacy Proceeding” (petition for formal probate of a will, or petition to set aside informal probate / to adjudicate intestacy), filed in the probate file in the circuit court under SDCL 29A-3-401 and 29A-3-402. Where a formal testacy order has already been entered, the filing is a petition to vacate the order and reopen the matter under SDCL 29A-3-412.

Objections to a pending formal petition are filed as written objections under SDCL 29A-3-404. Filing must be in the county of proper venue, and under SDCL 29A-1-303 the county where a proceeding is first commenced has the exclusive right to proceed.. Step four is discovery and, in most cases, a settlement conference; the small minority that reach trial are decided by a jury if requested.

Settling Instead of Fighting

YES. SDCL 29A-3-912 allows competent successors to agree in writing among themselves to alter the interests, shares, or amounts they are entitled to under the will or under intestacy, subject to the rights of creditors and taxing authorities; the personal representative must abide by the terms of such a written agreement executed by all affected parties.

In addition, SDCL 29A-3-1101 and 29A-3-1102 authorize court-approved compromises of controversies over the admission of a will to probate, the construction of a will, and the distribution of the estate — a compromise approved after notice and hearing binds all parties, including unborn, unascertained, and incapacitated persons represented in the proceeding. Circuit courts may also refer probate disputes to mediation.

Other South Dakota rules: (1) South Dakota is a full Uniform Probate Code state — Title 29A, adopted effective July 1, 1995 — so both informal (clerk/registrar) and formal (judicial) tracks exist, and which track was used determines which deadline applies. (2) The 12-month-from-informal-probate clock in SDCL 29A-3-108 is the trap: an heir who waits for the 3-year-from-death outer limit may already be barred if informal probate happened early.

Because the statute grants the LATER of the two, a will informally probated more than 2 years after death still gives a contestant the full 12 months.

(3) Self-proved wills — under SDCL 29A-2-504 a will made self-proved by the attached notarized affidavits of testator and witnesses is admitted without live witness testimony; under SDCL 29A-3-406 signature compliance is conclusively presumed and other execution requirements are presumed subject to rebuttal, absent proof of fraud or forgery affecting the acknowledgment or affidavit. This makes a pure “improper execution” attack on a self-proved South Dakota will difficult.

(4) South Dakota does NOT appear to offer ante-mortem (pre-death) judicial validation of a WILL; South Dakota’s well-known pre-death validation and no-contest machinery, including SDCL 55-1-46, sits in the trust statutes (SDCL 55-1 and SDCL 21-22), which is one reason many South Dakota estate plans are built around trusts rather than wills. Treat this as UNVERIFIED for wills specifically until confirmed with counsel.

(5) There is no separate probate court — everything is circuit court, and SDCL 29A-1-303 gives the first county in which a proceeding is commenced the exclusive right to proceed. (6) Notice of an informal probate is sent to heirs and devisees under SDCL 29A-3-306 after the fact, so the 12-month clock can begin before an heir has read the will.

(7) A jury right in a formal testacy proceeding under SDCL 29A-1-306 is unusual among UPC states and can materially change the strategy and cost of a South Dakota contest.

The Evidence That Wins or Loses a Will Contest

Capacity cases turn on the weeks around the signing: the medical chart, prescriptions, a dementia diagnosis, and what the drafting lawyer and the witnesses saw that day. A will signed in a lawyer’s office with two disinterested witnesses and a self-proving affidavit is hard to attack; a will signed at a kitchen table with the main beneficiary present is not.

Undue influence cases turn on the relationship — who drove the parent to the appointment, who chose the lawyer, who was in the room, and whether the new will departed sharply from earlier ones and from what the parent said to other people.

Improper execution is the narrowest ground and the cleanest: South Dakota sets exact witness and signature rules, and a will that misses them fails regardless of what the signer intended. Before you contest a will in South Dakota, gather the prior wills, the medical releases, and the names of everyone at the signing.

Most of that evidence has to be requested formally once the case is filed, and the deadline does not wait for it.

What to Expect When You Contest a Will in South Dakota

A will contest is a lawsuit about the document, not about fairness. When you contest a will in South Dakota, the court asks whether the person who signed it had capacity, signed it freely, and signed it correctly. It does not ask whether the split was reasonable. That is why the strongest cases rest on medical records and witness accounts from the weeks around the signing.

Most families who contest a will in South Dakota settle. Courts encourage it, many states have family settlement rules that let the heirs agree to a different division, and a settlement avoids the cost and delay of trial. The deadline, the grounds, and the no-contest clause above are the three facts that set your bargaining position before any of that begins.

You don’t have to do this alone

If you are settling a loved one’s estate in South Dakota, your state’s probate court self-help center and free legal-aid offices can walk you through the process at no cost. For an active probate or a deadline, talk to a licensed probate attorney in your state.

Key Takeaways: Contest a Will in South Dakota

The deadline is everything: the window to contest a will in South Dakota closes on a fixed schedule, and the court cannot reopen it for a late but valid claim.
Grounds are specific: you contest a will in South Dakota on capacity, undue influence, fraud, duress, or bad execution, never on unfairness alone.
Standing first: only an interested person can contest a will in South Dakota; check whether you inherit under the prior will or the intestate rules.
Read the no-contest clause: whether the state enforces it decides how much risk it takes to contest a will in South Dakota.
Evidence is medical and financial: records, witnesses to the signing, and the drafting lawyer’s file decide most cases when you contest a will in South Dakota.
Settlement is common: most families who contest a will in South Dakota settle before trial, often through the state’s family settlement rules.
Find the admission date: the day the will was admitted is the day the clock to contest a will in South Dakota usually starts.
Prior wills matter twice: they give you standing to contest a will in South Dakota and show how far the last will departed from the pattern.
Notice defects are a lifeline: if you never got the required notice, you may still contest a will in South Dakota after the ordinary deadline.
Self-proved wills are harder: a will with a notarized witness affidavit raises the bar to contest a will in South Dakota on execution grounds.
Cost scales with the estate: before you contest a will in South Dakota, compare the likely fees to what you would actually gain.
Mediation is usually offered: many courts require a settlement conference before anyone who chooses to contest a will in South Dakota sees a judge.

Official South Dakota Sources & Resources

South Dakota Probate Court: https://ujs.sd.gov (South Dakota Unified Judicial System); self-help and forms at https://ujs.sd.gov/Information/selfhelp.aspx; circuit court locations and clerk of courts contacts at https://ujs.sd.gov/Circuit_Courts/
South Dakota Will Contest Statute: https://sdlegislature.gov/Statutes/29A-3-108 (deadline); https://sdlegislature.gov/Statutes/29A-3-407 (grounds and burden of proof); https://sdlegislature.gov/Statutes/29A-3-905 (no-contest clause); https://sdlegislature.gov/Statutes/29A-3-401 (formal testacy petition); https://sdlegislature.gov/Statutes/29A-3-412 (effect of order and vacation); https://sdlegislature.gov/Statutes/29A-1-306 (jury trial); full chapter at https://sdlegislature.gov/Statutes/29A-3
Internal Revenue Service — Estate Tax: irs.gov
Cornell Legal Information Institute: law.cornell.edu/wex

This South Dakota guide was last verified against official sources in September 2026. Laws change — verify with your state court or a licensed attorney.

More South Dakota Estate Guides

Disclaimer: This guide is informational only and is not legal or tax advice. Estate, probate, and tax laws change and vary by state and county. Verify current rules and dollar figures with your state’s court, statute, or a licensed attorney or tax professional before acting. For urgent matters like an active probate or a tax deadline, consult a licensed professional in your state right away.

Estate planning? Make sure your life insurance is in order — see Life Insure Guide. Worried about Medicaid estate recovery? See Medicare Cover Guide. Divorced recently? Update your will and beneficiaries — see Divorce Help Guide.

How to Contest a Will in South Dakota — Deadline, Grounds, and Who Can File (2026)