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Registered agent worksheets · South Dakota

3 Best Registered Agents in South Dakota (2026): Worked Prices

Worked out for 2026, the best-value registered agents in South Dakota come to Mainstay Filing ($149/yr), South Dakota Registered Agent.co ($99/yr) and SD Registered Agent.org ($99/yr), in that order. The rows start at $99 to $149 for the first year and total $297 to $447 after three.
Worked by the Formation Math editorial team

↓ Sorted by: Cost first (42%), items covered second (28%), three smaller checks after. See the working

The working so far

Registered agent compulsory? Yes sdlegislature.gov (checked October 2026) as the source
Year 1 spread $99 to $149 Price for the year
Three-year results $297 to $447 First year + 2 renewals
Annual report $55 a year sdlegislature.gov (checked October 2026) as the source
Crossing point No crossing The order stays put for ten years

The South Dakota rows

Service prices only. The state charges the same no matter which agent you name.

1
Highest score

1. Mainstay Filing: best for LLCs operating in more than one state

$149/yr now, $149/yr at renewal
Year-1 price $149
Renewal price $149/yr
Sum of 3 years $447

Row one is Mainstay Filing. The math: $149 a year now and in whichever state the company registers next.

South Dakota Registered Agent.co totals $150 less over three years, but the 28% coverage term favors this row.

The price buys

  • A street address in the state
  • Three government mailings per year, scanned for free
  • Works for LLCs, corporations, LPs, LLPs and nonprofits

Adds up

  • Fifty-state reach
  • $149 every year

Does not add up

  • A yearly gap of $50
  • Agent service only, so reports stay with you
2
Built for South Dakota

2. South Dakota Registered Agent.co: best for the smallest annual agent total

$99/yr now, $99/yr at renewal
Year-1 price $99
Renewal price $99/yr
Sum of 3 years $297

Next in the working, South Dakota Registered Agent.co: $99 yearly, including an in-state street address on file.

The price buys

  • A local registered office
  • Scans of papers served on the LLC

Adds up

  • Year 1 $99, year 2 $99
  • Undercuts Mainstay Filing each year

Does not add up

  • No help outside the state
  • This row does not reach the annual report
3
Built for South Dakota

3. SD Registered Agent.org: best for another in-state option

$99/yr now, $99/yr at renewal
Year-1 price $99
Renewal price $99/yr
Sum of 3 years $297

Next in the working, SD Registered Agent.org: $99 yearly, including an in-state street address on file.

Compare the two and the figures match: South Dakota Registered Agent.co charges the same.

The price buys

  • A local registered office
  • Scans of papers served on the LLC

Adds up

  • Undercuts Mainstay Filing each year
  • Year 1 $99, year 2 $99

Does not add up

  • No help outside the state
  • This row does not reach the annual report

Totals after 1, 2, 3 and 5 years

No. Provider Year 1 total Total at year 2 Total at year 3 Total at year 5
1 Mainstay Filing $149 $298 $447 $745 Visit Mainstay Filing Partner link. We may earn money if you buy.
2 South Dakota Registered Agent.co $99 $198 $297 $495 Visit South Dakota Registered Agent.co Partner link. We may earn money if you buy.
3 SD Registered Agent.org $99 $198 $297 $495 Visit SD Registered Agent.org Partner link. We may earn money if you buy.

Service fees only, using each company's prices as read on November 13, 2026. None of the rows cross in ten years.

Try your own number of years

The calculator adds year one and the renewals for every row once you choose the years.

Adding up 3 years: Mainstay Filing $447, South Dakota Registered Agent.co $297, SD Registered Agent.org $297. The least spent: South Dakota Registered Agent.co.

The state's side of the math, South Dakota

Term Value Where it comes from
Cost to form $150 sdlegislature.gov (checked October 2026) as the source
Annual report $55 every year sdlegislature.gov (checked October 2026) as the source
Cost of missing the deadline $50 sdlegislature.gov (checked October 2026) as the source
State fees added over 3 years $260 Calculated from the rows above

Working: filing fee, plus the recurring report in years two and three, plus any minimum tax. The sum is the three-year state line.

What settled the order

Items covered per dollar put Mainstay Filing in row one. That term is 28% of the score; three-year total, year-two change, crossover year and published detail make up the rest.

On coverage across states, South Dakota Registered Agent.co cannot match it.

South Dakota registered agent rules, from the source (South Dakota Secretary of State)

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. Look up SDCL 59-11-6.

The address has to be an actual street address or rural route box number in South Dakota, plus a South Dakota mailing address if it differs.

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

Filing it yourself, worked out

A qualifying owner can name themselves and pay no agent fee; state fees do not change. The rows above charge $99 to $149 a year for a South Dakota address and someone to accept legal papers.

Questions

What does a registered agent in South Dakota cost per year?

$99 to $149 a year in this table.

What do three years of agent service cost?

$297 to $447 across the rows, not counting state fees.

Does South Dakota require a registered agent for an LLC?

Yes. Every LLC must name a registered agent with an in-state street address.

Can the owner be the registered agent?

Yes, when you qualify under the rules listed here.

What does the state collect from the LLC each year?

South Dakota expects the annual report every year at $55, due during the entity's anniversary month.

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

Not within ten years; no row passes another.

Which registered agent is best value in South Dakota?

From the top: Mainstay Filing, South Dakota Registered Agent.co and SD Registered Agent.org.

See also

Registered agent worksheets, all 50 states Best registered agents overall The method

Inputs and sources

  1. South Dakota Secretary of State, per sdsos.gov, August 2026.
  2. South Dakota Secretary of State, per sosenterprise.sd.gov, August 2026.
  3. South Dakota yearly filing: Annual, per sdlegislature.gov, October 2026.
  4. South Dakota report due date, per sdlegislature.gov, August 2026.
  5. SDCL 47-34A-203, per sdlegislature.gov, August 2026.
  6. South Dakota formation fee: Filing, per sdsos.gov, October 2026.
  7. South Dakota formation fee: Filing, per sdlegislature.gov, October 2026.
  8. South Dakota registered agent statute, per sdlegislature.gov, October 2026.
  9. November 13, 2026 copy of the Mainstay Filing South Dakota service page
  10. November 13, 2026 copy of the South Dakota Registered Agent.co pricing page
  11. November 13, 2026 copy of the SD Registered Agent.org pricing page