How to Start a South Dakota LLC: Step by Step

Your LLC's name has to be distinguishable from every other business entity already on file with the South Dakota Secretary of State. "Distinguishable" is a legal test, not just a gut check: a name that differs only by punctuation, spacing, or a filler word like "the" or "and" may not clear it. The Secretary of State checks against all registered entities, not just LLCs.

Start with the state's business filing search. Run your proposed name and any close variations. If something too similar already exists, the state can reject your Articles, costing you time.

Naming rules to know

• Under SDCL 47-34A-105, the name must contain "limited liability company" or "limited company," or the abbreviation "L.L.C.," "LLC," "L.C.," or "LC." "Limited" may be abbreviated "Ltd." and "company" may be "Co."
• It cannot imply a purpose the LLC isn't authorized for, and words like "bank," "trust," or "insurance" may require approval from the relevant regulator.
• It cannot falsely suggest affiliation with a government agency.
• It must be distinguishable from every active name in the Secretary of State's records.

Reserving a name

If you have the perfect name but aren't ready to file, South Dakota lets you reserve it for 120 days by filing a name reservation with the Secretary of State, and the fee is $25. This holds the name without forming the LLC, which is useful while you sort out financing, partners, or a lease. Plan the timing, because SDCL 47-34A-106 bars the same applicant from reserving the same name again until 60 days after the reservation expires.

Operating under a different name (DBA)

If you'll do business under a name other than your LLC's legal name, South Dakota calls that a fictitious or assumed name. You can register it with the Secretary of State online, or at the county Register of Deeds, where the registration runs on a five-year term. This is a separate step from forming the LLC.

Before you file the Articles of Organization, you need a registered agent chosen and willing to serve. Under SDCL 59-11-6, naming an agent in the Articles affirms that the agent has consented, so ask first.

Every South Dakota LLC must maintain a registered agent for as long as the company exists, and the Secretary of State's FAQ says the agent must be a South Dakota resident with both a physical and a mailing address in the state. The agent is who receives lawsuits, subpoenas, regulatory notices, and official Secretary of State correspondence on the company's behalf.

Who can be your registered agent

South Dakota sorts agents into two types under its Model Registered Agents Act (SDCL chapter 59-11):

• Yourself, as a noncommercial agent: if you live in South Dakota and have an actual street address there plus a mailing address. Your address becomes part of the public record.
• Another individual or a business entity, as a noncommercial agent: any South Dakota resident (a co-owner, an employee, an attorney, a trusted friend) or a business entity registered in South Dakota.
• A commercial registered agent: a company registered with the Secretary of State as a commercial registered agent, listed on your Articles by name and CRA number. It keeps its professional address on the public record instead of yours and forwards documents to you promptly.

Why it matters which you choose

If you list your home as the agent address, it's searchable by anyone who looks up your LLC. Owners who work from home, travel often, or simply value privacy usually prefer a commercial agent so their personal address stays off the public database and there's never a gap in coverage.

The Articles of Organization is the document that legally creates your LLC in South Dakota. File it online through the Secretary of State's business services portal. The state fee is $150 online and $165 on paper (the extra $15 is South Dakota's paper processing fee for documents that can be filed online), and the portal takes Visa, MasterCard, Discover and American Express.

The Secretary of State's FAQ says online filings are processed immediately, and the color PDF certificate is ready to download once payment clears. New paper filings average 1 to 3 business days, and expedited paper service costs $50. For nearly everyone, online is the right call.

What the Articles include

• LLC name: your full legal name with the required LLC designator.
• Designated office address: in or out of South Dakota, with an optional email address.
• Registered agent: a noncommercial agent with a South Dakota street address and mailing address, or a commercial registered agent by name and CRA number.
• Organizers: the name and address of each organizer, who sign the Articles.
• Duration: only if the LLC won't be perpetual.
• Management structure: member-managed or manager-managed (with the managers' names and addresses).
• Optional items: a purpose statement, beneficial owners, and other provisions.

What you don't have to disclose

You don't have to list members' names or ownership percentages, describe your business activities in depth, or reveal any financial details. The Articles are a short formation document, not a disclosure filing. The private internal details live in your operating agreement.

An operating agreement is your LLC's internal rulebook. South Dakota doesn't require you to file it, and it never enters any public database, but you should have one in place before you start doing business, add members, or open accounts.

What a solid operating agreement covers

• Ownership: who the members are and each member's percentage interest.
• Capital contributions: what each member put in at the start and any obligation to contribute more later.
• Profit and loss allocation: how gains and losses are split among members (usually, but not always, matching ownership percentages).
• Distributions: when and how cash gets paid out.
• Management: who runs day-to-day operations and which decisions require a member vote.
• Voting: whether votes track ownership percentage or work some other way.
• Transfers: what happens when a member wants to sell or leave, including rights of first refusal.
• Dissolution: how the company winds down and distributes assets if it ends.

For a single-member LLC, the agreement reinforces that the company is a genuine separate entity, something courts weigh when someone challenges the liability shield. For a multi-member LLC, it's indispensable: without it, South Dakota's statutory defaults govern everything, and those defaults may not reflect what the members agreed to.

An Employer Identification Number is a nine-digit federal tax ID from the IRS, issued at no cost. It works like a Social Security number for the business. You use it on tax filings, to open bank accounts, and to hire employees.

When you need one

• Your LLC has more than one member (a multi-member LLC files a partnership return and must have an EIN).
• You plan to hire employees.
• You want a business bank account (nearly every bank requires an EIN).
• You've elected S-corp or C-corp tax treatment.

A single-member LLC with no employees can technically use the owner's SSN, but getting an EIN keeps your Social Security number off business paperwork and makes banking easier, so most owners get one anyway.

How to apply

Use the online IRS EIN Assistant over at IRS.gov to file your request. It takes about ten minutes and the number is issued immediately, so you can use it the same day. Online applications need a US Social Security number or ITIN; applicants without one file Form SS-4 by fax or mail.

A separate business bank account isn't optional if you want the liability shield to hold. Mixing personal and business money (paying personal bills from the company account or depositing business income into a personal one) gives a court a reason to disregard the LLC and hold you personally liable.

What most banks want

• Your filed Articles of Organization from the Secretary of State
• Your IRS EIN confirmation
• Your operating agreement (many banks ask for it)
• Government-issued ID for every authorized signer

Local South Dakota banks and credit unions often onboard new LLCs more smoothly than national chains, and several online business banks can open an account without a branch visit. Look at each option's monthly charges, its caps on transactions, and the balance it expects you to maintain before making your choice.

Once you're formed, ongoing compliance in South Dakota is light: mostly one annual filing plus keeping your agent and address current.

Annual report

Your annual report is due on the first day of your LLC's anniversary month each year, beginning the year after you form. You can file it up to 2 months before that date, for $55 online or $70 on paper. The report confirms your principal office, registered agent, and (for a manager-managed LLC) governors, plus whether the company owns agricultural land, with no financial reporting. There's no penalty the day after the due date: the $55 late fee applies once the report is 2 months past due, and if it still isn't filed, the Secretary of State can start administrative dissolution.

From January 1, 2027, South Dakota adds an option: an LLC can choose a fixed January 31 due date each year instead of its anniversary month, selected on the formation document or switched later with a change-of-filing-date form.

Keep your registered agent current

If your agent moves, resigns, or you switch providers, file a Statement of Change with the Secretary of State promptly. The fee is $10, plus $15 if you file it on paper. An outdated agent address puts your LLC out of compliance even if everything else is in order.

Taxes

Federally, a single-member LLC files Schedule C, a multi-member LLC files Form 1065, and an S-corp election files Form 1120-S. South Dakota has no state income tax on pass-through entities. If you sell taxable goods or services, register for a sales tax license with the South Dakota Department of Revenue.

Licenses and permits

South Dakota has no general statewide business license, but many professions require specific licensure, and some cities require local registration. These run on their own cycles, separate from your LLC filing.