Partnership and LLC default rules in South Dakota

What happens when you start a business in South Dakota without a written agreement.

South Dakota at a glance

Partnership law

RUPA (revised)

LLC default split

Equal per-capita

Operating agreement

Not required

Community property

Opt-in available

Formation cost

$150

Annual cost

$50 annual report fee

South Dakota has no state income tax and offers opt-in community property through a community property trust. The state is known for business-friendly laws and strong trust and asset protection statutes.

Default partnership rules in South Dakota

South Dakota adopted RUPA, treating partnerships as separate entities with equal profit sharing by default. Partners have equal management rights and owe fiduciary duties.

The most important takeaway: profits are split equally by default in South Dakota, regardless of capital contributions. If you and a partner start a business and one of you invests $100,000 while the other invests $5,000, you still split profits 50/50 without a written agreement. This is true in every US state, including South Dakota.

LLC defaults in South Dakota

South Dakota follows RULLCA, defaulting to equal per-capita distributions among members regardless of capital contributions. An operating agreement is not required. The state has no income tax, so LLC income is only taxed at the federal level.

Because South Dakota follows RULLCA with equal per-capita defaults, LLC members should pay special attention to their operating agreement. Without one, a member who contributed 90% of the capital gets the same share of profits as a member who contributed 10%. Use our equity calculator to determine a fair split based on actual contributions.

What happens when a partner leaves in South Dakota

Under South Dakota's RUPA, a partner's departure does not dissolve the partnership. The partnership continues, and the departing partner is entitled to a buyout at fair value.

A written partnership agreement should still address departure terms specifically, including how the buyout value is calculated, the payment timeline, and any non-compete provisions. While RUPA provides a default framework, the details of a buyout can still lead to disputes if not spelled out in advance. Understanding the concept of dead equity is important for managing these situations. Learn more about how dead equity affects businesses.

Marriage and business equity in South Dakota

South Dakota is an equitable distribution state but offers opt-in community property through a community property trust. Without the opt-in, business interests are divided equitably in a divorce. With the opt-in, selected assets can be treated as community property for estate planning purposes.

South Dakota offers opt-in community property, which means couples can elect community property treatment for specific assets. Business owners should be aware that opting in could affect their business interests and should consult an attorney before making this election.

Formation and cost considerations in South Dakota

Formation cost $150
Annual/recurring cost $50 annual report fee
State income tax No
Partnership law RUPA (revised) — partnership continues after departure
LLC default distributions Equal per-capita (RULLCA) — all members get equal share
Operating agreement Not required (strongly recommended)

Frequently asked questions

Does South Dakota have a state income tax?

No. South Dakota has no state income tax, making it attractive for business formation. LLC income is only taxed at the federal level.

Does South Dakota offer community property?

South Dakota offers opt-in community property through a community property trust. This is not the default and requires an affirmative election. It is primarily used for estate planning purposes.

What is the default LLC profit split in South Dakota?

South Dakota follows RULLCA, defaulting to equal per-capita distributions. All members get the same share regardless of capital contributions unless an operating agreement says otherwise.

How much does a South Dakota LLC cost?

South Dakota LLC formation costs $150, and the annual report fee is $50. There is no state income tax, keeping overall costs low.

Related resources

Disclaimer: This page provides general information about South Dakota partnership and LLC default rules and is not legal advice. Laws change, and the information here may not reflect the most recent amendments. The formation costs and annual fees listed are approximate and may vary. Consult a qualified attorney licensed in South Dakota for advice specific to your situation. Equity Matrix is a software tool for tracking contributions and calculating equity; it does not provide legal services.

Replace South Dakota's defaults with a fair agreement.

Equity Matrix tracks contributions and calculates ownership automatically, so your agreement reflects what your team actually built together.