3 Best LLC Services in South Dakota (2026): The Straight Story
South Dakota, 2026: Mainstay Filing ($199), South Dakota Registered Agent.co ($199) and SD Registered Agent.org ($199) are our picks for LLC formation services, in that order. Every option pays the same $150 filing fee, then three years of service cost $397 to $597.
Straight from the LLC Straight Talk editorial team
The short of it
The short of it
What the state charges
$150, one time
Every year after
$55 a year
Registered agent
Yes, it's the law
Who we'd use
Mainstay Filing, South Dakota Registered Agent.co then SD Registered Agent.org
South Dakota: our ranking
The order comes from our five tests: three-year cost first, then what the price covers.
#1Our top pick
1. Mainstay Filing: best for handing off the upkeep
$199 a year and $150 to the state
Mainstay Filing wins the top spot: $199 a year pays for forming the LLC, acting as your registered agent and filing the annual report, and it renews at $199.
Here's the catch: South Dakota Registered Agent.co costs $200 less over three years, and you'd do more of the paperwork yourself.
It files your annual report, and South Dakota's $55 gets passed along at cost.
What you get
Formation handled start to finish
Registered agent for twelve straight months
Annual report taken care of when due
EIN application
State fees at cost
Pluses
The EIN application's included
Renews at $199
$199 yearly, everything listed
What's not
$100 a year above South Dakota Registered Agent.co after year one
#2South Dakota specialist
2. South Dakota Registered Agent.co: best for a business that never leaves one state
$199 plus the state fee, then $99 a year
South Dakota Registered Agent.co comes in second because $199 gets your LLC formed, and then the agent's $99 a year.
Filing the annual report isn't covered, so that job's yours.
What you get
South Dakota formation filing
Agent service covered for year one
Pluses
Renewal's $99
Starts at $199 over the state fee
The first agent year's included
What's not
You're stuck filing the annual report
The EIN application costs $99 extra
#3South Dakota specialist
3. SD Registered Agent.org: best for another in-state choice
$199 plus the state fee, then $99 a year
SD Registered Agent.org comes in third because $199 gets your LLC formed, and then the agent's $99 a year.
Filing the annual report isn't covered, so that job's yours.
Price for price, it's a tie with South Dakota Registered Agent.co.
What you get
South Dakota formation filing
Agent service covered for year one
Pluses
Renewal's $99
The first agent year's included
Starts at $199 over the state fee
What's not
You're stuck filing the annual report
The EIN application costs $99 extra
The numbers
#
Company
First year
Then
Three-year total
What you get
1
Mainstay Filing
$199
$199/yr
$597
formation handled start to finish; registered agent for twelve straight months; annual report taken care of when due
Read November 13, 2026. Three years is year one plus two renewals.
The questions that matter
What's it cost to form an LLC here?
Figure $150 for the state, plus $199 if you hire help in year one.
Add the recurring report and the state's fees reach $260 over three years. go check sdlegislature.gov, last confirmed October 2026
Which form do I file, and where?
Here's what starts the company: the Articles of Organization, sent to the South Dakota Secretary of State.
How long the state takes: Paper 1 to 3 business days; online processed immediately. go check sdlegislature.gov, last confirmed October 2026
Does the state make me have 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.
You'll file the annual report every year, and it's $55 each time. Here's the date the state gives: due during the entity's anniversary month. Don't miss it.
Yes. Filing it yourself costs only the state's fees: $260 over three years.
A service adds $397 to $597 over three years, and with Mainstay Filing the reports are in that price.
What put number one on top?
Mainstay Filing scores best on jobs the price actually covers, and that test is worth 30%.
We run five tests: money out the door in three years (35%), jobs the price actually covers (30%), no hunting for the price (14%), no surprise at renewal (11%) and where it works (10%).
We'd rather have the annual report filed for us than save a few bucks.
The last row is our math, not the state's: filing fee, plus the reports in years two and three, plus any minimum tax. If a cost has no fixed amount, like a newspaper notice, it's explained above and left out.
Still wondering?
When will my LLC exist?
Paper 1 to 3 business days; online processed immediately.
Is the EIN application included?
Mainstay Filing includes the EIN application. The others make you pay: South Dakota Registered Agent.co $99; SD Registered Agent.org $99.
What if I'm late with the report?
Expect a $50 late fee.
What do the picks cost over three years?
Over three years you're looking at $597 at Mainstay Filing, $397 at South Dakota Registered Agent.co, $397 at SD Registered Agent.org, services only.
Are the fees official?
Official South Dakota sources back the state side, and posted prices back the service side.
What's the best LLC service in South Dakota?
Mainstay Filing, because one yearly price of $199 covers the formation, the registered agent and every annual report. After that, South Dakota Registered Agent.co and SD Registered Agent.org.