Can a sole proprietor become an LLC in South Dakota?

Yes. A sole proprietorship is not a legal entity separate from its owner, so you convert by forming a new South Dakota LLC and moving the business into it. File your Articles of Organization with the South Dakota Secretary of State and pay the filing fee ($150 online, $165 on paper). On the EIN, the IRS says a single-member LLC can keep using your sole proprietor EIN if it does not choose corporate or S-Corporation tax treatment, has no employees and owes no excise tax; otherwise it needs its own EIN, which you apply for on Form SS-4. Move the business's accounts and contracts into the LLC's name, update your business licenses with the city or county where you operate, and check whether any state tax registrations must be reissued in the LLC's name. Forming the LLC gives you limited liability protection that a sole proprietorship lacks. Confirm current fees and submission requirements with the South Dakota Secretary of State before filing.

Does forming an LLC reduce self-employment tax in South Dakota?

No, forming a South Dakota LLC doesn't by itself reduce self-employment tax. By default, a single-member LLC is taxed like a sole proprietorship and a multi-member LLC like a partnership, and the owners generally owe 15.3% self-employment tax on net self-employment earnings. Self-employment tax is a federal tax paid to the IRS, not to a state agency: it is 12.4% for Social Security, which applies only up to an annual earnings cap, plus 2.9% for Medicare. However, an eligible LLC can file Form 2553 (Election by a Small Business Corporation) with the IRS to be taxed as an S-Corporation. You then pay yourself a reasonable salary, which is subject to Social Security and Medicare payroll taxes, and take remaining profits as distributions, which are not. The trade-off: an S-Corporation must run payroll, file payroll tax returns and a separate federal return (Form 1120-S), and pay for the accounting that requires. Whether the tax savings exceed those costs depends on your profits. Next step: consult a South Dakota CPA to model the savings based on your projected income before filing Form 2553.

How much does it cost to form an LLC in South Dakota?

South Dakota's state filing fee to form an LLC is $150 if you file your Articles of Organization online with the South Dakota Secretary of State, or $165 on paper. South Dakota LLCs also file an annual report each year starting the year after formation, at $55 online or $70 on paper, and a delinquent report adds a $55 penalty. South Dakota has no corporate income tax and no franchise tax on an LLC's earnings. Every South Dakota LLC must have a registered agent, and an individual, including you, can serve as a noncommercial registered agent under South Dakota's Model Registered Agents Act. If you use a paid service to form the LLC, Northwest Registered Agent charges $39 plus the state fee with a year of registered agent service included, and ZenBusiness charges $0 plus the state fee, with registered agent service at $99 for the first year when you form with them. File your Articles of Organization with the South Dakota Secretary of State to get started.

Does an LLC protect personal assets in South Dakota?

Yes. Under South Dakota law, a South Dakota LLC's debts, obligations and other liabilities are solely the company's, and a member or manager is not personally liable for them solely by reason of being or acting as a member or manager. That protection has limits: it covers liability that arises only from your role as a member, so it does not cover, for example, a debt you personally guarantee. South Dakota law also says that an LLC's failure to observe formalities in exercising its powers or managing its activities and affairs is not a ground for holding a member or manager liable for the LLC's debts, so skipping meetings or minutes is not, by itself, a ground for losing your protection. Keeping a separate business bank account and never mixing personal and business funds are still sensible practices, because courts can in some cases disregard an LLC and reach its owners ("piercing the veil"), and commingled funds invite that argument. If a creditor wins a judgment against your LLC for a company obligation you did not guarantee, it generally collects from the LLC's assets, not your personal home and savings. To secure this protection, file your Articles of Organization with the South Dakota Secretary of State and open a dedicated business bank account from day one.

Can one person own an LLC in South Dakota?

Yes, South Dakota allows an LLC with a single member, and that one person can own and manage it. For federal tax purposes, the IRS treats a single-member LLC as a disregarded entity by default, so the LLC's income is reported on your personal return, just as with a sole proprietorship. An eligible LLC can instead elect S-Corporation tax treatment by filing Form 2553 with the IRS, which can reduce self-employment taxes on profits taken as distributions. The practical benefit: you gain personal liability protection for business debts while keeping tax filing simple. To form one, file your Articles of Organization with the South Dakota Secretary of State and pay the filing fee ($150 online, $165 on paper). The IRS says a single-member LLC with no employees, no excise tax and no corporate tax election can use your sole proprietor EIN instead of getting a new one.

Is a sole proprietorship legal in South Dakota without registration?

Yes, a sole proprietorship doesn't have to file formation documents in South Dakota. You become a sole proprietor when you start doing business on your own, with no filing at the South Dakota Secretary of State. There are still caveats. Check with your city or county whether your type of business needs a local license, since local requirements and fees vary. South Dakota requires anyone regularly doing business under a name that does not plainly show the true surname of each owner to file a fictitious name statement, either electronically with the Secretary of State or on paper with any register of deeds, for a $10 fee, renewed every fifth year. Certain professions, such as health practitioners, need specific state licenses from their licensing boards, and a business that sells taxable goods or services generally needs a sales tax registration. The practical implication: while you avoid state formation fees, you remain personally liable for all business debts and legal judgments, unlike an LLC owner. Your next step: contact your city or county to confirm licensing requirements and fees for your specific business type and location.

South Dakota LLC vs Sole Proprietorship: Complete 2026 Guide

Compare an LLC and a sole proprietorship in South Dakota: liability, taxes, costs and paperwork.

By Edmond Hui · Last updated: October 2026

In South Dakota, an LLC fits when you have personal assets to protect from business liabilities and lawsuits; a sole proprietorship fits when you're testing a low-risk business idea with minimal startup costs. Compare both structures in detail below.

Read this guide for another state:

Affiliate disclosure: We may earn a commission at no extra cost to you.

Form your LLC with Northwest ($39 + state fee)Includes a year of registered agent service. After year one, registered agent service is $125/yr. That enrolls you by default in annual report filing at $100 plus state fees, charged automatically to your saved payment method and cancellable any time.

Not sure which service is right? Compare formation services →

Comparison chart for South Dakota LLC versus Sole Proprietorship, contrasting liability, taxation and ongoing filing burden across 8 factors. — Side-by-side on the factors that decide the choice, for South Dakota. Source: South Dakota Secretary of State.

LLC vs Sole Proprietorship: Side-by-Side

Factor	LLC	Sole Proprietorship
Personal liability protection	Limited liability: members are not personally liable for the LLC's debts and obligations solely because they are members	No protection: you're personally liable for all business debts and legal claims
Formation cost & paperwork	$150 South Dakota filing fee online ($165 on paper) for Articles of Organization with the Secretary of State	No state formation filing required, just start doing business
Taxation	Pass-through by default (no double taxation), with the option to elect corporate or S-Corporation tax treatment	Pass-through only: all business income is reported on your personal return (Schedule C)
Self-employment tax	15.3% self-employment tax on net self-employment earnings by default (Social Security part capped yearly); an S-Corp election may reduce it at higher profits	15.3% self-employment tax on net self-employment earnings, with the Social Security part capped each year; a sole proprietorship cannot elect S-Corp status
Business credibility	Professional appearance with 'LLC' designation helps with customers, vendors, and lenders	May appear less established: operates under your personal name or a trade name
Banking & contracts	Separate business bank account recommended to keep LLC and personal funds apart; easier to get business credit cards and loans	Can use personal accounts, though a separate account makes business records and taxes easier to track
State fees in South Dakota	$150 one-time filing fee online ($165 on paper), plus a $55 annual report online ($70 on paper) each year, starting the year after formation	$0: no state formation filing required (a name that does not show your surname needs a $10 fictitious name statement)
Conversion path to LLC	Already an LLC: can elect different tax treatments as the business grows	You can form a South Dakota LLC later by filing Articles of Organization with the South Dakota Secretary of State

When an LLC Makes More Sense

You have personal assets to protect from business liabilities and lawsuits
You want professional credibility and easier access to business banking and credit
Your profits are high enough that an S-Corp election's self-employment tax savings would outweigh the added payroll and accounting costs
You plan to have business partners or investors in the future

When a Sole Proprietorship Makes More Sense

You're testing a low-risk business idea with minimal startup costs
Your business has low liability risk (like freelance writing)
You want to avoid the $150 South Dakota filing fee, the $55 annual report and LLC paperwork
Your income is modest and you want maximum tax simplicity

Tax Deep Dive

Sole Proprietorship Tax

Sole proprietorships report business income on Schedule C of your personal federal return. You pay regular income tax plus 15.3% self-employment tax on net self-employment earnings, with the 12.4% Social Security part applying only up to an annual earnings cap, and a sole proprietorship cannot elect S-Corporation tax treatment.

LLC Default Tax

By default, a single-member LLC is a 'disregarded entity' for federal tax purposes, taxed like a sole proprietorship, and a multi-member LLC is taxed as a partnership. Either way, you generally still owe self-employment tax on net self-employment earnings, but an LLC can elect a different tax treatment as your business grows.

LLC S-Corp Election

South Dakota LLCs can elect S-Corporation tax status to split income into a reasonable salary (subject to Social Security and Medicare payroll taxes) and distributions (not subject to those taxes). Whether it saves money depends on your profits and the added payroll and accounting costs, so have a CPA model it before electing.

This guide is general information, not legal or tax advice, and reading it does not create an attorney-client relationship. It reports published tax rates and statutory attributes, with the sources this page cites. It cannot tell you which structure is better for you: that turns on your profit, the salary you could defend as reasonable compensation, every state you owe tax in, and plans for owners, investors and exit that no figure on this page measures. Confirm your own position with a CPA or tax attorney licensed in your state before you elect anything, because some elections are slow or costly to reverse.

Frequently Asked Questions

: Yes. A sole proprietorship is not a legal entity separate from its owner, so you convert by forming a new South Dakota LLC and moving the business into it. File your Articles of Organization with the South Dakota Secretary of State and pay the filing fee ($150 online, $165 on paper). On the EIN, the IRS says a single-member LLC can keep using your sole proprietor EIN if it does not choose corporate or S-Corporation tax treatment, has no employees and owes no excise tax; otherwise it needs its own EIN, which you apply for on Form SS-4. Move the business's accounts and contracts into the LLC's name, update your business licenses with the city or county where you operate, and check whether any state tax registrations must be reissued in the LLC's name. Forming the LLC gives you limited liability protection that a sole proprietorship lacks. Confirm current fees and submission requirements with the South Dakota Secretary of State before filing.
: No, forming a South Dakota LLC doesn't by itself reduce self-employment tax. By default, a single-member LLC is taxed like a sole proprietorship and a multi-member LLC like a partnership, and the owners generally owe 15.3% self-employment tax on net self-employment earnings. Self-employment tax is a federal tax paid to the IRS, not to a state agency: it is 12.4% for Social Security, which applies only up to an annual earnings cap, plus 2.9% for Medicare. However, an eligible LLC can file Form 2553 (Election by a Small Business Corporation) with the IRS to be taxed as an S-Corporation. You then pay yourself a reasonable salary, which is subject to Social Security and Medicare payroll taxes, and take remaining profits as distributions, which are not. The trade-off: an S-Corporation must run payroll, file payroll tax returns and a separate federal return (Form 1120-S), and pay for the accounting that requires. Whether the tax savings exceed those costs depends on your profits. Next step: consult a South Dakota CPA to model the savings based on your projected income before filing Form 2553.
: South Dakota's state filing fee to form an LLC is $150 if you file your Articles of Organization online with the South Dakota Secretary of State, or $165 on paper. South Dakota LLCs also file an annual report each year starting the year after formation, at $55 online or $70 on paper, and a delinquent report adds a $55 penalty. South Dakota has no corporate income tax and no franchise tax on an LLC's earnings. Every South Dakota LLC must have a registered agent, and an individual, including you, can serve as a noncommercial registered agent under South Dakota's Model Registered Agents Act. If you use a paid service to form the LLC, Northwest Registered Agent charges $39 plus the state fee with a year of registered agent service included, and ZenBusiness charges $0 plus the state fee, with registered agent service at $99 for the first year when you form with them. File your Articles of Organization with the South Dakota Secretary of State to get started.
: Yes. Under South Dakota law, a South Dakota LLC's debts, obligations and other liabilities are solely the company's, and a member or manager is not personally liable for them solely by reason of being or acting as a member or manager. That protection has limits: it covers liability that arises only from your role as a member, so it does not cover, for example, a debt you personally guarantee. South Dakota law also says that an LLC's failure to observe formalities in exercising its powers or managing its activities and affairs is not a ground for holding a member or manager liable for the LLC's debts, so skipping meetings or minutes is not, by itself, a ground for losing your protection. Keeping a separate business bank account and never mixing personal and business funds are still sensible practices, because courts can in some cases disregard an LLC and reach its owners ("piercing the veil"), and commingled funds invite that argument. If a creditor wins a judgment against your LLC for a company obligation you did not guarantee, it generally collects from the LLC's assets, not your personal home and savings. To secure this protection, file your Articles of Organization with the South Dakota Secretary of State and open a dedicated business bank account from day one.
: Yes, South Dakota allows an LLC with a single member, and that one person can own and manage it. For federal tax purposes, the IRS treats a single-member LLC as a disregarded entity by default, so the LLC's income is reported on your personal return, just as with a sole proprietorship. An eligible LLC can instead elect S-Corporation tax treatment by filing Form 2553 with the IRS, which can reduce self-employment taxes on profits taken as distributions. The practical benefit: you gain personal liability protection for business debts while keeping tax filing simple. To form one, file your Articles of Organization with the South Dakota Secretary of State and pay the filing fee ($150 online, $165 on paper). The IRS says a single-member LLC with no employees, no excise tax and no corporate tax election can use your sole proprietor EIN instead of getting a new one.
: Yes, a sole proprietorship doesn't have to file formation documents in South Dakota. You become a sole proprietor when you start doing business on your own, with no filing at the South Dakota Secretary of State. There are still caveats. Check with your city or county whether your type of business needs a local license, since local requirements and fees vary. South Dakota requires anyone regularly doing business under a name that does not plainly show the true surname of each owner to file a fictitious name statement, either electronically with the Secretary of State or on paper with any register of deeds, for a $10 fee, renewed every fifth year. Certain professions, such as health practitioners, need specific state licenses from their licensing boards, and a business that sells taxable goods or services generally needs a sales tax registration. The practical implication: while you avoid state formation fees, you remain personally liable for all business debts and legal judgments, unlike an LLC owner. Your next step: contact your city or county to confirm licensing requirements and fees for your specific business type and location.

Sources

10 documents

Each entry below is a document recorded in our verified South Dakota sources, and each entry says what the document is. Some statutory text is read from an accurate mirror rather than from the state's own host, and those say so. Where we hold the citation but no stable public link, the citation is printed on its own rather than pointed at a guessed address.

sdlegislature.gov/Statutes/47-34A-303SDCL 47-34A-303, liability of members and managers
sdlegislature.gov/Statutes/59-11-2SDCL 59-11-2, definitions, Model Registered Agents Act (noncommercial registered agent)
sdlegislature.gov/Statutes/37-11-1SDCL 37-11-1, filing of fictitious name statement
irs.gov/businesses/small-businesses-self-employed/self-employment-tax-social-security-and-medicare-taxesIRS, Self-employment tax (Social Security and Medicare taxes)
irs.gov/businesses/small-businesses-self-employed/do-you-need-a-new-einIRS, Do you need a new EIN?
South Dakota statute: SDCL 47-34A-303(b) (company formalities)
South Dakota statute: SDCL 47-34A-303(a) (member and manager liability)
South Dakota statute: SDCL 37-11-1 (fictitious name statement)
sdsos.gov/business-services/corporations/default.aspxSouth Dakota Secretary of State: business entity filings
sdsos.gov/general-information/filing-fees.aspxSouth Dakota LLC filing fees

More for South Dakota LLCs

Start and set up

Taxes, money and growth

Stay compliant

Operate in other states

Compare structures

By owner type

By profession

Forming an LLC in South Dakota?

See how Northwest Registered Agent, Bizee, ZenBusiness and LegalZoom, the formation services we partner with, compare on 3-year cost, BBB rating and Trustpilot score before you choose.

Compare Services →

Ready to Form Your South Dakota LLC?

Affiliate disclosure: We may earn a commission at no extra cost to you.

Not sure which service is right? Compare formation services →

Edmond Hui · Founder, MyStateLLC

Edmond Hui is a software engineer and serial entrepreneur based in New York who has founded multiple online businesses across e-commerce, media, and information publishing. Before transitioning into tech, he spent years as a commercial real estate professional closing deals totaling over 100,000 square feet, giving him firsthand experience with business formation and entity structuring. He built MyStateLLC to provide the free, state-specific LLC guidance he wished existed when forming his own companies.

How we check facts

LLC vs Sole Proprietorship: Side-by-Side

When an LLC Makes More Sense

When a Sole Proprietorship Makes More Sense

Tax Deep Dive

Sole Proprietorship Tax

LLC Default Tax

LLC S-Corp Election

Frequently Asked Questions

Sources

More for South Dakota LLCs

Start and set up

Taxes, money and growth

Stay compliant

Operate in other states

Compare structures

By owner type

By profession

Ready to Form Your South Dakota LLC?

More South Dakota LLC Guides

Related guides