3 Best Foreign Registration Services in South Dakota (2026), Step by Step
In South Dakota for 2026, compare South Dakota Registered Agent.co ($199), Mainstay Filing ($199) and SD Registered Agent.org ($199), ranked best first. Registration at the state costs $750 for every filer, and three years of service fees add $397 to $497.
Written by the Simple Filing Guide editorial team
The short route
What you pay the state
$750
Paper from your home state?
Yes, attach it
Later on
$55, annual report
First choices
South Dakota Registered Agent.co, Mainstay Filing then SD Registered Agent.org
Our South Dakota shortlist
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 one extra state
Year one $199; later years $99
Start with South Dakota Registered Agent.co in South Dakota: $199 files the registration, and the agent renews at $99 each year.
Cost decides this one, since the three-year bill is lower than at Mainstay Filing.
Across three years the state's total comes to $860. sdsos.gov, confirmed October 2026, official source
Where does the registration go?
File the Application for Certificate of Authority, Foreign Limited Liability Company with the South Dakota Secretary of State. That single filing registers the LLC.
The filing needs certificate of Existence.
What does staying registered cost?
After registering, expect the annual report: $55.
The state sets the deadline at 1st of the anniversary month.
Why is number one first?
South Dakota Registered Agent.co leads on total for three years, which carries 37% of our score.
Five checks set the order: total for three years (37%), filing jobs included (27%), clear price information (13%), year-two price (12%) and state coverage (11%).
Choose South Dakota Registered Agent.co over Mainstay Filing and keep $100 across three years.
Every amount above links to its official source. The last row is our own total of the filing, two reports and any minimum tax, without variable costs like publication.
Related questions
Do both states require an agent?
You do: two states mean two sets of rules, and one-state services stop at the border while Mainstay Filing does not.
Three years in, what has each cost?
South Dakota Registered Agent.co adds up to $397, Mainstay Filing adds up to $497, SD Registered Agent.org adds up to $397, and state fees are separate.
Are the fees official?
For state costs we use South Dakota's published fee schedules and forms. For service costs we use each company's price page.
Do I have to use a service?
If you meet the rules on this page, you can file on your own, and the state charges the same either way.
Do these companies handle the filing?
All of them do, and the state fee stays identical.
Which foreign registration service should I start with in South Dakota?
South Dakota Registered Agent.co leads on total for three years, ahead of Mainstay Filing and SD Registered Agent.org.
Sources used in this guide
Source for South Dakota Secretary of State: sdsos.gov, August 2026