Foreign registration ratings · South Dakota
3 Best Foreign Registration Services in South Dakota (2026)
1. SD Registered Agent.org: best for adding South Dakota and nothing else
Service fee $199, state fee on top; agent $99 a year after that
SD Registered Agent.org is rated first: $199 on top of the state fee to register in South Dakota, agent at $99 afterward.
The plan lists an in-state street address as the registered office and scans papers served there into your account.
On three-year sums it comes out ahead of Mainstay Filing.
What you get
- The registration filing
- The first year as your registered agent
Pros
- Registers the company for $199 plus state fees
- Then $99 yearly for the agent
- A year of registered agent service is in the price
Trade-offs
- South Dakota only; your home state needs its own agent
- EIN application billed at $99
2. Mainstay Filing: best for companies registered in more than one state
Service fee $199, with $949 due at checkout including the state fee; agent $149 a year after that
Mainstay Filing is rated second: $199 plus state fees in any state, first-year registered agent service included.
The agent line is $149 a year from year two, identical across states, after a free first year.
SD Registered Agent.org is $100 cheaper on the three-year sum, and that lowers Mainstay Filing's cost rating.
What you get
- The registration, prepared and filed for you
- A free first year of registered agent service
- No-fee scans of service of process on the day it is received
Pros
- $199 service fee, state fee separate
- Registered agent, no charge in year one
- The same amount in all fifty states
- Same-business-day scans of service of process, no fee
Trade-offs
- Agent renewal of $149 is $50 over SD Registered Agent.org
3. South Dakota Registered Agent.co: best for South Dakota registrations only
Service fee $199, state fee on top; agent $99 a year after that
South Dakota Registered Agent.co is rated third: $199 on top of the state fee to register in South Dakota, agent at $99 afterward.
The plan lists an in-state street address as the registered office and scans papers served there into your account.
On amounts and features alone, SD Registered Agent.org and South Dakota Registered Agent.co are the same, which makes the order between them a close call.
What you get
- The registration filing
- The first year as your registered agent
Pros
- Agent line of $99 from year two
- First-year registered agent service is included
- $199 service fee and the registration fee
Trade-offs
- South Dakota only; your home state needs its own agent
- EIN application billed at $99
The 3 ratings summarized
| Line | Service | Rating | Service fee | Year two | Best for | Open |
|---|---|---|---|---|---|---|
| 1 | SD Registered Agent.org | 9.5 | $199 | $99/yr | The lowest agent renewal we rank here | Visit SD Registered Agent.orgPartner link. We may earn money if you buy. |
| 2 | Mainstay Filing | 9.1 | $199 | $149/yr | Companies that register in several states | Visit Mainstay FilingPartner link. We may earn money if you buy. |
| 3 | South Dakota Registered Agent.co | 8.9 | $199 | $99/yr | The lowest agent renewal we rank here | Visit South Dakota Registered Agent.coPartner link. We may earn money if you buy. |
South Dakota foreign registration service amounts for 2026: year one, renewal and three-year sum
| Service | Year one | Year two | Year three | Three-year sum | Agent paid for year one |
|---|---|---|---|---|---|
| SD Registered Agent.org | $199 | $99 | $99 | $397 | Included |
| Mainstay Filing | $199 | $149 | $149 | $497 | Free |
| South Dakota Registered Agent.co | $199 | $99 | $99 | $397 | Included |
How the lines were rated
Formation Rated puts 27% on cost over years one to three, 27% on inclusions per price and the other 46% on renewal price and terms, fit with state rules and price clarity. In South Dakota the order came down to cost over years one to three.
SD Registered Agent.org sums to $397 across three years, $100 below Mainstay Filing. Both services include year one of agent service, so the renewal amount decided the order.
Each criterion and its weight is listed on How we rank.
South Dakota foreign LLC registration: amount, form and office
A company from another state registers by lodging the Application for Certificate of Authority, Foreign Limited Liability Company with the South Dakota Secretary of State; the state amount is $750. South Dakota also needs certificate of Existence.
Registration adds one recurring line: the annual report ($55), due 1st of the anniversary month.
Have these ready
- Certificate of Existence.
- Home-state legal name, spelled exactly, and the formation date.
- An in-state registered agent; every service rated here can fill the role.
- $750 to the state, paid with the filing.
- The date of the annual report and its $55 fee on your calendar.
What skipping South Dakota registration costs
Contracts it signs remain valid (SDCL 47-34A-1008(b)).
South Dakota foreign registration service: your questions
Is registration compulsory for an outside LLC doing business in South Dakota?
Yes, once it does business there.
What are the costs of foreign registration in South Dakota?
$750 to the state plus $199 to the service.
Must the filing include a home-state certificate for South Dakota?
Yes: certificate of Existence.
Must a registered agent stay on file after registering?
Yes. A registered agent with a street address in the state stays on record.
Which foreign registration services are rated on this page?
SD Registered Agent.org ($199), Mainstay Filing ($199) and South Dakota Registered Agent.co ($199), highest rated first.
Which foreign registration service holds the top rating in South Dakota?
SD Registered Agent.org, as $199 plus the state fee, year-one registered agent service included, then $99 a year for the agent.
Source lines
- South Dakota Secretary of State, Business Services / Corporations Division (ledger date August 2026)
- South Dakota Secretary of State, Business Services / Corporations Division (ledger date August 2026)
- South Dakota yearly filing: Annual report: fee and how, official source (ledger date October 2026)
- South Dakota report due date (ledger date August 2026)
- SDCL 47-34A-203 (ledger date August 2026)
- South Dakota formation fee: Filing fee, official source (ledger date October 2026)
- South Dakota formation fee: Filing fee, official source (ledger date October 2026)
- South Dakota registered agent statute (ledger date October 2026)
- South Dakota Secretary of State, business services (ledger date October 2026)
- Foreign LLC application for Certificate of Authority (ledger date October 2026)
- SDCL 47-34A-1003, transacting business (ledger date October 2026)
- SDCL 47-34A-1008, effect of not registering (ledger date October 2026)
- SDCL 47-34A-1001 to 47-34A-1009, foreign limited liability companies (ledger date November 2026)
- SD Registered Agent.org, pricing and service pages: amounts read November 12, 2026
- Mainstay Filing, South Dakota service page: amounts read November 12, 2026
- South Dakota Registered Agent.co, pricing and service pages: amounts read November 12, 2026