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Foreign registration worksheets · South Dakota

3 Best Foreign Registration Services in South Dakota (2026): Worked Prices

The 2026 math for South Dakota foreign registration services gives Mainstay Filing ($199), SD Registered Agent.org ($199) and South Dakota Registered Agent.co ($199), ranked best value first. The state's $750 is common to all rows. What differs is the service total, $397 to $497 over three years.
Worked by the Formation Math editorial team

↓ Sorted by: Score = 42% three-year total + 28% coverage + three smaller terms (details)

Results box

Fee the state takes to register $750 sdsos.gov (checked October 2026) as the source
Year 1 spread $199 Without the state fee
Totals after three years $397 to $497 Year one plus two more years
What the state collects by year 3 $860 Does not depend on the row
First crossover Does not occur No change in order

South Dakota rows with the arithmetic

Service prices only. Add the $750 state fee to any row; it is identical for all.

1
Highest score

1. Mainstay Filing: best for adding a second or third state

$199 on top of the state's $750; renewals at $149
Year-1 price $199
Price after year 1 $149/yr
Sum of 3 years $497

Mainstay Filing comes out on top. Working: $199 to file, no agent charge in year one, and the same price in each state.

The $100 three-year premium over SD Registered Agent.org buys coverage, and coverage decides this ranking.

Renewals for the agent are $149 a year, whichever state you pick.

The price buys

  • Registration papers, prepared and filed
  • Registered agent with no charge in year one
  • One fee wherever you register

Adds up

  • $199 added to South Dakota's fee
  • The first agent year is covered
  • Covers all fifty states

Does not add up

  • SD Registered Agent.org charges $50 less for the agent
2
Built for South Dakota

2. SD Registered Agent.org: best for the smallest annual agent total

$199 on top of the state's $750; renewals at $99
Year-1 price $199
Price after year 1 $99/yr
Sum of 3 years $397

SD Registered Agent.org fills row 2: registration in South Dakota costs $199 here, with a $99 agent renewal after that.

The price buys

  • Filing delivered to the state
  • Year-one agent service

Adds up

  • Starts at $199
  • Agent renews at $99
  • Agent service free in year one

Does not add up

  • The home state still needs a different agent
3
Built for South Dakota

3. South Dakota Registered Agent.co: best for a second in-state filer

$199 on top of the state's $750; renewals at $99
Year-1 price $199
Price after year 1 $99/yr
Sum of 3 years $397

South Dakota Registered Agent.co fills row 3: registration in South Dakota costs $199 here, with a $99 agent renewal after that.

Its prices equal SD Registered Agent.org's in every column.

The price buys

  • Filing delivered to the state
  • Year-one agent service

Adds up

  • Agent service free in year one
  • Starts at $199
  • Agent renews at $99

Does not add up

  • The home state still needs a different agent

Cumulative cost, year by year

No. Provider Year 1 total Total at year 2 Total at year 3 Total at year 5
1 Mainstay Filing $199 $348 $497 $795 Visit Mainstay Filing Partner link. We may earn money if you buy.
2 SD Registered Agent.org $199 $298 $397 $595 Visit SD Registered Agent.org Partner link. We may earn money if you buy.
3 South Dakota Registered Agent.co $199 $298 $397 $595 Visit South Dakota Registered Agent.co Partner link. We may earn money if you buy.

Company prices from November 13, 2026, summed year by year. The totals keep one order for ten years.

Try your own number of years

Pick a number of years and each row's running sum appears.

Sum after 3 years: Mainstay Filing $497, SD Registered Agent.org $397, South Dakota Registered Agent.co $397. Smallest total: SD Registered Agent.org.

South Dakota state fees (official)

Term Value Where it comes from
Cost to register $750 sdsos.gov (checked October 2026) as the source
Annual report $55 sdlegislature.gov (checked October 2026) as the source
State side, 3 years $860 Filing + reports + any tax

To get the three-year state figure, add the filing fee, the reports due in years two and three, and any yearly minimum tax. Costs with no fixed amount, such as newspaper publication, are mentioned but not added.

What settled the order

For South Dakota, the term that decided it was items covered per dollar (28% of the score), where Mainstay Filing came out ahead.

The home state counts too; covering both with one account scored highest.

South Dakota foreign LLC registration fee and rules, from the source

Doing business in South Dakota through an LLC from another state takes the Application for Certificate of Authority, Foreign Limited Liability Company, filed at the South Dakota Secretary of State for $750. Add certificate of Existence.

Quoted from: sdlegislature.gov (checked October 2026) as the source

If you skip the service

The state's fees alone total $860 for three years, which is the floor. The table shows what each service adds ($397 to $497).

Quick answers

How much does South Dakota take to register an out-of-state LLC?

$750 as the official fee, before service fees of $199.

What do the services add up to over three years?

$397 to $497 across the rows, not counting state fees.

Which form does the registering?

The form is Application for Certificate of Authority, Foreign Limited Liability Company, and the South Dakota Secretary of State receives it.

Does South Dakota ask for a paper from the home state?

Yes: certificate of Existence.

What recurring filing comes after registration?

The annual report, which costs $55.

In what year does one service pass another in total cost?

Not within ten years; no row passes another.

Which foreign registration service is best value in South Dakota?

Mainstay Filing scores first. SD Registered Agent.org and South Dakota Registered Agent.co follow.

Next worksheets

Foreign registration worksheets, all 50 states Best foreign registration services overall The method

Inputs and sources

  1. Source of South Dakota Secretary of State: sdsos.gov, August 2026.
  2. Source of South Dakota Secretary of State: sosenterprise.sd.gov, August 2026.
  3. Source of South Dakota yearly filing: Annual: sdlegislature.gov, October 2026.
  4. Source of South Dakota report due date: sdlegislature.gov, August 2026.
  5. Source of SDCL 47-34A-203: sdlegislature.gov, August 2026.
  6. Source of South Dakota formation fee: Filing: sdsos.gov, October 2026.
  7. Source of South Dakota formation fee: Filing: sdlegislature.gov, October 2026.
  8. Source of South Dakota registered agent statute: sdlegislature.gov, October 2026.
  9. Source of South Dakota Secretary of State: sdsos.gov, October 2026.
  10. Source of Foreign LLC application for Certificate: sdsos.gov, October 2026.
  11. Source of SDCL 47-34A-1003, transacting business: sdlegislature.gov, October 2026.
  12. Source of SDCL 47-34A-1008, effect of not: sdlegislature.gov, October 2026.
  13. Source of SDCL 47-34A-1001 to 47-34A-1009, foreign: sdlegislature.gov, November 2026.
  14. The Mainstay Filing South Dakota service page supplied the prices on November 13, 2026
  15. The SD Registered Agent.org pricing page supplied the prices on November 13, 2026
  16. The South Dakota Registered Agent.co pricing page supplied the prices on November 13, 2026