3 Best LLC Services in South Dakota (2026), Ranked for You
Start with this 2026 ranking of LLC formation services in South Dakota: South Dakota Registered Agent.co ($199), SD Registered Agent.org ($199) and Mainstay Filing ($199), in that order. The costs split into $150 for the state and $397 to $597 for three years of service.
Written by the Simple Filing Guide editorial team
Four facts to know
Fee at the state
$150, not recurring
Later years
$55 on a yearly schedule
Registered agent
You must
Recommended
South Dakota Registered Agent.co, SD Registered Agent.org then Mainstay Filing
South Dakota: the ranking
Prices come from each company's own page. Read how we rank for the method.
#1First recommendation
1. South Dakota Registered Agent.co: best for a one-state LLC
$199 plus the state fee, then $99 a year
Why South Dakota Registered Agent.co first? Because forming costs $199, the agent is covered in year one, and then $99 a year.
Compare the three-year totals: it lands under Mainstay Filing, and cost is the check we weigh most.
The annual report is not in the price, so add it to your own checklist.
3. Mainstay Filing: best for owners who want upkeep handled
$199 yearly ($349 at signup, state fee included)
Mainstay Filing is third, because its $199 yearly price pays for forming the LLC, serving as the registered agent and filing the annual report, and renews at $199.
Three years here run $200 higher than South Dakota Registered Agent.co.
Filing the annual report is part of the service, and only the state's $55 is added.
Checklist: what is included
LLC formation filed with the state
Registered agent for a full year
Annual report filed on time
EIN request filed
State fee with no markup
What works
Year two costs $199
EIN application included in the price
Everything above is included in $199
Gaps
South Dakota Registered Agent.co undercuts its renewal by $100
These are service fees only, taken from each company's prices on November 13, 2026. State fees stay the same with every pick.
Questions to settle
What will forming an LLC cost in this state?
Set aside $150 for the filing and $199 for help.
Over three years the state collects $260 in total, filing fee included. official source sdlegislature.gov (October 2026) to check
Who receives the filing?
Submit the Articles of Organization to the South Dakota Secretary of State and wait for approval.
Expected wait: Paper 1 to 3 business days; online processed immediately. official source sdlegislature.gov (October 2026) to check
Can the LLC go without 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.
Add the filing fee, the reports for years two and three and any minimum tax to reproduce the last row. Costs with no set amount, such as a newspaper notice, are left out.
Also asked
How quickly does the state approve it?
Paper 1 to 3 business days; online processed immediately.
Does the price cover the EIN?
Mainstay Filing includes the EIN application. The others charge extra: South Dakota Registered Agent.co $99; SD Registered Agent.org $99.
What happens if I miss the report?
South Dakota adds $50 for lateness.
What is the three-year cost of each?
Totals to compare: South Dakota Registered Agent.co at $397, SD Registered Agent.org at $397, Mainstay Filing at $597, and state fees are separate.
Are the fees official?
Official South Dakota documents supply the state fees, and the companies' own pricing pages supply the service fees. Both carry dates on this page.
Who ranks first in South Dakota?
Choose South Dakota Registered Agent.co first, then compare SD Registered Agent.org and Mainstay Filing.
Sources and price pages
Source for South Dakota Secretary of State: sdsos.gov, August 2026