South Dakota Elective Share: How Spousal Inheritance Protection Works

South Dakota law prevents you from completely disinheriting your spouse. Even if your will leaves everything to your children, your business partner, or a charitable organization, your surviving spouse has the legal right to claim a percentage of your estate — and the calculation includes assets you may have thought were untouchable.

The Sliding Scale

Under SDCL 29A-2-202, the elective share percentage depends on how long you were married:

• Less than 1 year: No percentage share, but a $50,000 minimum floor applies
• 1–5 years: 3% per year (3% at 1 year, rising to 15% at 5 years)
• 5–10 years: Continues climbing by 3% per year (up to 30% at 10 years)
• 10–15 years: Increases by 4% per year (up to 46% at 14 years)
• 15+ years: 50% of the augmented estate

For a marriage of 15 years or longer, your spouse is entitled to half of everything — not half of what you chose to leave them, but half of the entire augmented estate.

What Counts as the Augmented Estate

This is where the calculation surprises people. The "augmented estate" under SDCL 29A-2-202 is not just the probate estate. It includes:

• Everything in your probate estate (assets passing through your will or by intestacy)
• Assets in revocable trusts
• Joint bank accounts and joint tenancies
• Life insurance proceeds (in certain circumstances)
• Transfers made shortly before death
• The surviving spouse's own assets and non-probate transfers

The augmented estate concept was designed to prevent a simple workaround: moving everything into joint accounts, trusts, or beneficiary designations to leave the probate estate empty and the spouse with nothing. Under South Dakota's system, those transfers are pulled back into the calculation.

The $50,000 Minimum Floor

If the elective share calculation (including assets the spouse already owns and any devises under the will) produces a total below $50,000, the surviving spouse is entitled to a supplemental elective share up to $50,000. This supplemental amount comes from the decedent's probate estate and, if that's insufficient, from non-probate transferees.

This floor exists to protect surviving spouses in short marriages where the percentage would otherwise produce a trivially small amount.

How the Elective Share Interacts with Your Estate Plan

The elective share is a right the surviving spouse must actively claim — it does not happen automatically. The spouse files a petition with the court within nine months of the decedent's death (or six months after probate is admitted, whichever is later).

If the surviving spouse does not file, the will's provisions stand as written. Many spouses never file because the will already provides generously. The elective share becomes relevant primarily in two situations:

1. Intentional disinheritance: The deceased spouse's will excludes the surviving spouse or leaves them a token amount
2. Blended family conflicts: The will favors children from a prior marriage at the expense of the current spouse

Planning Around the Elective Share

You cannot eliminate the elective share through estate planning tricks. Revocable trusts, beneficiary designations, and pre-death transfers are all captured by the augmented estate calculation. South Dakota's system was specifically designed to close those loopholes.

What you can do:

• Postnuptial agreements: Spouses can voluntarily waive elective share rights through a properly executed written agreement (SDCL 29A-2-213). Both parties should have independent legal counsel.
• Prenuptial agreements: Same principle, executed before marriage.
• Transparent planning: If your estate plan intentionally provides less than the elective share to your spouse, discuss it openly. Many couples agree to an arrangement that favors children from prior marriages, but that agreement needs to be documented as a formal waiver.

The Omitted Spouse Rule

A related protection under SDCL 29A-2-301: if you execute a will and then marry without updating it, your new spouse is entitled to an intestate share of your estate — the same share they would receive if you died without a will. This applies automatically unless the will shows you intentionally made no provision for a future spouse, or unless a prenuptial agreement waives the right.

The practical takeaway: update your will after every marriage. The South Dakota Basic Estate Planning Kit includes guidance on the elective share implications for different family structures and a will execution framework that accounts for these spousal protection rules.

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