Open it up · South Dakota

3 Best LLC Services in South Dakota (2026), Opened Up

South Dakota, 2026: Mainstay Filing ($199), South Dakota Registered Agent.co ($199) and SD Registered Agent.org ($199), in that order, are the LLC formation services worth opening first. Inside the cost: $150 goes to the state, and three years of service add $397 to $597.

Unpacked by the LLC Unpacked editorial teamUpdated November 13, 2026

Four things inside

Fee to the state: $150, one time
Next layer: $55 each year
Registered agent: Required, yes
Top of the stack: Mainstay Filing, South Dakota Registered Agent.co then SD Registered Agent.org

The South Dakota stack, best on top

Prices come from each company's own page. See how we open it up.

Top of the stack

1. Mainstay Filing: best for not filing the annual report yourself

$199 a year, with the $150 state fee added

Mainstay Filing is first, and $199 a year packs in formation, the registered agent and every annual report.

Over three years this runs $200 above South Dakota Registered Agent.co, and more of the filings are handled inside.

You never file the annual report. South Dakota still charges $55, billed at cost.

Inside the price

Formation filed with the state
Registered agent across the full year
Annual report filed on your behalf
EIN application handled
State fees at cost

Inside, the good

$199 a year covers filing, agent and report
The EIN application is inside the price
Year two costs $199

Inside, the catch

Renews $100 higher than South Dakota Registered Agent.co

South Dakota only

2. South Dakota Registered Agent.co: best for a business that stays in one state

$199 to form; renewal $99

What puts South Dakota Registered Agent.co second: it opens at $199 with the first agent year inside and renews at $99.

You still file the annual report yourself.

Inside the price

The LLC, filed for you
A first year of agent service

Inside, the good

No agent charge in year one
Then $99 yearly
$199 to form the LLC

Inside, the catch

The annual report is a job you keep
The EIN application costs $99 extra

South Dakota only

3. SD Registered Agent.org: best for another in-state option

$199 to form; renewal $99

What puts SD Registered Agent.org third: it opens at $199 with the first agent year inside and renews at $99.

You still file the annual report yourself.

Its prices match South Dakota Registered Agent.co exactly, so the order between them is close.

Inside the price

The LLC, filed for you
A first year of agent service

Inside, the good

No agent charge in year one
Then $99 yearly
$199 to form the LLC

Inside, the catch

The annual report is a job you keep
The EIN application costs $99 extra

Inside each price

#	Pick	Year one	Each year after	Total, 3 years	Covers
1	Mainstay Filing	$199	$199/yr	$597	formation filed with the state; registered agent across the full year; annual report filed on your behalf	See Mainstay FilingPartner link. We may earn money if you buy.
2	South Dakota Registered Agent.co	$199	$99/yr	$397	The LLC, filed for you; A first year of agent service	See South Dakota Registered Agent.coPartner link. We may earn money if you buy.
3	SD Registered Agent.org	$199	$99/yr	$397	The LLC, filed for you; A first year of agent service	See SD Registered Agent.orgPartner link. We may earn money if you buy.

Service fees only, from company prices read November 13, 2026. State fees are the same whichever pick you open.

Opened up, question by question

How much does forming an LLC cost in this state?

Filing costs $150. A service on top of that costs $199 in year one.

Across three years the state collects $260, filing fee included. peek at sdlegislature.gov, confirmed October 2026

Which form is inside the filing, and where does it go?

The South Dakota Secretary of State receives the Articles of Organization, and once it is approved the company exists.

Expect this wait: Paper 1 to 3 business days; online processed immediately. peek at sdlegislature.gov, confirmed October 2026

Must the LLC name a registered agent?

Every LLC must name a registered agent with an in-state street address.

A commercial registered agent listed with the state, a noncommercial agent (an individual or entity with a South Dakota address), or the title of an office in the company.

peek at sdlegislature.gov, confirmed October 2026

What comes after the LLC is formed?

Underneath it all, one filing repeats: the annual report, every year, at $55 each time. The state phrases its deadline like this: due during the entity's anniversary month.

File late and the state adds $50.

peek at sdlegislature.gov, confirmed October 2026

Can I file it myself instead of hiring a service?

Nothing stops you. Without a service, your three-year bill is the state's $260.

Services add $397 to $597 across three years to take the filings off your desk, and Mainstay Filing counts the reports among them.

Why is the stack in this order?

Mainstay Filing is strongest on what is inside the price, a layer worth 29% of the score.

Two layers carry most of the weight, total across three years (34%) and what is inside the price (29%).

A filed annual report outweighs a small saving, in our weighing.

How we open it up

South Dakota: the formation checklist

Requirement	Amount or rule	Peek at source
LLC filing fee	$150	peek at sdlegislature.gov, confirmed October 2026
Registered agent	Required, yes	peek at sdlegislature.gov, confirmed October 2026
Annual report	$55 every year	peek at sdlegislature.gov, confirmed October 2026
State fees, years one to three	$260	The rows above, stacked

The last row stacks the filing fee, the reports in years two and three and any minimum tax. A cost with no fixed amount, such as a newspaper notice, is explained above and kept out of the sum.

More boxes to open

How long does the state take?

Paper 1 to 3 business days; online processed immediately.

Is the EIN application inside the price?

Only Mainstay Filing packs it in. Elsewhere it is $99 at South Dakota Registered Agent.co and $99 at SD Registered Agent.org.

What if the report is late?

Expect a $50 late fee.

How do the three-year totals compare?

Mainstay Filing runs to $597 and South Dakota Registered Agent.co runs to $397 and SD Registered Agent.org runs to $397, before state fees.

What do these numbers rest on?

Official South Dakota paperwork stands behind every state fee here, and every service price traces back to the company's own pricing.

Who tops the stack in South Dakota?

Mainstay Filing is on top: the annual report is filed for you within the $199 annual price, next to formation and the registered agent. Under it sit South Dakota Registered Agent.co and SD Registered Agent.org.

What the page rests on

Under South Dakota Secretary of State sits sdsos.gov, dated August 2026, as the original document
Under South Dakota Secretary of State sits sosenterprise.sd.gov, dated August 2026, as the original document
Under South Dakota yearly filing: Annual sits sdlegislature.gov, dated October 2026, as the original document
Under South Dakota report due date sits sdlegislature.gov, dated August 2026, as the original document
Under SDCL 47-34A-203 sits sdlegislature.gov, dated August 2026, as the original document
Under South Dakota formation fee: Filing sits sdsos.gov, dated October 2026, as the original document
Under South Dakota formation fee: Filing sits sdlegislature.gov, dated October 2026, as the original document
Under South Dakota registered agent statute sits sdlegislature.gov, dated October 2026, as the original document
Under Processing, official source sits sdsos.gov, dated October 2026, as the original document
Mainstay Filing South Dakota service page, read November 13, 2026
South Dakota Registered Agent.co pricing page, read November 13, 2026
SD Registered Agent.org pricing page, read November 13, 2026