How to Get an EIN in South Dakota: Free IRS

A South Dakota EIN is free, issued by the IRS the same day you apply through its online EIN Assistant, as of 2026. South Dakota has no income tax and no state withholding account. So once your South Dakota LLC is approved, the real state step is a Department of Revenue sales tax license, plus Reemployment Assistance once you hire.

Does Your South Dakota LLC Need an EIN?

Most South Dakota LLCs need an EIN, though not every one is federally required to hold it. Here’s how it breaks down by structure.

A single-member South Dakota LLC with no employees is a disregarded entity for federal tax, so the IRS doesn’t force it to carry an EIN. Even then, banks ask for one to open an account, and it keeps your Social Security number off vendor paperwork.

Multi-member LLCs are different: the IRS treats them as partnerships by default, and a partnership return needs its own number. A clear South Dakota operating agreement keeps those federal filings clean while members settle ownership.

If you’re weighing a DIY filing against a formation service, our South Dakota LLC comparison lays out the trade-offs.

How to Apply for Your South Dakota LLC’s EIN Online, Step by Step

The online application is the fastest route, and most South Dakota owners finish in one sitting once the LLC is approved, which depends on South Dakota’s filing turnaround. The IRS tool runs a short interview; here’s each step in practice.

1. Confirm the LLC is approved: the Secretary of State should show it active, so the legal name matches the CP 575.
2. Open the IRS EIN Assistant: it’s open weekdays 6 a.m. to 1 a.m. ET plus weekend hours, and the session closes after 15 minutes of inactivity, not at a set completion time.
3. Select the entity type: the screen that trips people up; a standard LLC isn’t a corporation unless you’ve filed an election.
4. Enter the legal name and any trade name: match the Articles of Organization exactly, then add a DBA only if you use one.
5. Name the responsible party: a natural person with an SSN or ITIN, never your registered agent or another entity.
6. Choose the reason and submit: pick “started a new business,” review every field, and send it.
7. Download the CP 575 immediately: save and print it on the spot; the IRS won’t reissue it, and you’d request a 147C letter instead.

International applicants whose principal place of business sits outside the U.S. call 267-941-1099, weekdays 6 a.m. to 11 p.m. ET; a faxed SS-4 takes about four business days, and a mailed form roughly four weeks.

The EIN itself is free. Third-party sites charge $150 to $300 to file Form SS-4 for you, but they’re reselling a federal service the IRS provides at no cost.

One limit catches people forming several entities at once: the IRS issues only one EIN per responsible party per day, across every method.

South Dakota EIN Approval: Save Your CP 575 Before You Register State Tax Accounts

When the IRS approves your South Dakota LLC’s EIN online, the confirmation appears as a CP 575 notice. Save it immediately, because this is the document banks, payroll providers, and state tax registrations may ask for when they need proof of your federal EIN.

What the approval letter confirms

The CP 575 shows the LLC’s legal name, mailing address, federal EIN, and IRS-assigned tax classification details. Keep it separate from your South Dakota sales tax license number, EPath login, and Reemployment Assistance account, because those are state-level records, not your federal EIN.

Sample IRS CP 575 EIN confirmation letter for a South Dakota LLC.

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Do this before moving on: download and print the CP 575 as soon as the EIN appears. If you lose the original confirmation later, the IRS generally verifies the EIN with Letter 147C instead of reissuing the original CP 575 notice.

What to Have Ready Before You Apply in South Dakota

Pulling a few details together first keeps the IRS interview quick. None of it’s complicated, but the name has to match your state record exactly.

• Approved legal name: word for word as it appears on your South Dakota Articles of Organization.
• Formation details: the LLC’s South Dakota filing record and formation date.
• Responsible party: full name plus SSN or ITIN.
• Entity type and reason: how the LLC is taxed, and why you’re applying.
• Business address: a South Dakota address works best for state matching.

Boost Suite recommends forming the LLC first, then applying, so the name on the CP 575 matches the state record. Applying before approval can leave a mismatch you’ll fix later, often while a bank waits on you.

Still setting up? The Articles of Organization run $150 online; our cost breakdown lists every fee, and a dependable registered agent keeps your state mail in one place.

EIN vs Your South Dakota Sales Tax License Number

A South Dakota LLC can end up holding several numbers, and they’re easy to mix up. The EIN is federal; the rest come from separate state agencies.

The South Dakota Secretary of State is clear that it doesn’t issue or store FEINs; that’s the IRS’s job. You can confirm your formation record any time with the South Dakota business entity search, which sits apart from anything federal.

Registering for South Dakota Sales Tax and Reemployment Assistance

Here’s where South Dakota gets specific. With no income tax, there’s no withholding account to set up; the state layer is sales tax, online filing, and unemployment coverage instead.

South Dakota Sales and Use Tax License

Any business with a physical presence in South Dakota must be licensed to collect sales and use tax. It reaches further than owners expect: goods, products transferred electronically, and services, all taxed at the 4.2% state rate as of 2026.

Remote sellers cross the line above $100,000 in gross sales into South Dakota; the old 200-transaction trigger ended July 1, 2023. That same 4.2% rate is scheduled to sunset after June 30, 2027 unless lawmakers extend it.

You register through the South Dakota Tax License Application. The DOR has historically charged no fee for a sales or contractor’s excise license, though it’s worth confirming inside the current application first.

Filing Through South Dakota EPath

EPath is the state’s online filing and payment portal, where sales tax returns get submitted once you’re licensed. One EPath account can carry several licenses, as long as they all share the same FEIN.

Reemployment Assistance With the South Dakota DLR

South Dakota calls its unemployment program Reemployment Assistance, run by the Department of Labor and Regulation. An employer becomes subject after paying $1,500 or more in wages in a calendar quarter, or employing someone in 20 different weeks.

New non-construction employers pay a 1.20% RA rate on the first $15,000 of each worker’s wages in 2026, while construction starts much higher. You sign up through Register Your Business and report via the Internet Quarterly Wage Reporting System.

Special South Dakota Taxes to Watch

A few South Dakota taxes apply only to certain work. Contractors owe a 2% contractor’s excise tax on gross receipts. Lodging and recreation businesses collect a 1.5% tourism tax, and many cities add a municipal sales tax of 1% to 2%.

Those municipal rates shift on their own schedule; South Shore jumps from 1% to 2% on July 1, 2026, so use the DOR municipal rate lookup for your city. Financial institutions separately owe South Dakota’s bank franchise tax.

Avoid These South Dakota EIN and Sales Tax Registration Mistakes

A few errors come up again and again, and they’re the kind that cost you a refile or a wrong state registration. Here are the ones worth dodging in South Dakota.

• Wrong entity classification: marking the LLC as a corporation on the SS-4 with no election filed forces a correction.
• Naming a nominee: the responsible party has to be a real person, not your registered agent or a holding entity.
• Applying twice: the one-per-day limit means a duplicate request simply bounces back.
• Name mismatch: if the EIN name doesn’t match the Secretary of State record, banks and the DOR push back.
• Assuming South Dakota income tax exists: some guides still list “file South Dakota income tax” as an EIN use, and there’s no such tax here.
• Trusting the old nexus rule: the “$100,000 or 200 transactions” line is stale; for 2026 it’s gross sales over $100,000 alone.

How to Find a Lost EIN or Update Your South Dakota LLC

Misplacing the CP 575 happens, and it’s not a crisis. The EIN itself never changes; you just need a reliable way to confirm it.

Your number shows up on past federal returns, prior bank paperwork, and any 1099s you’ve filed. For an official copy, ask the IRS for a 147C verification letter, the standard way to recover a forgotten EIN once the original notice is gone.

Some changes need a new EIN; most don’t. Converting a sole proprietorship to an LLC, or moving from single-member to multi-member, usually requires a fresh number, while a name or address change uses Form 8822-B or Form 8832.

After the EIN, your South Dakota LLC keeps filing on its own schedule. The state expects a South Dakota annual report each year, which holds the entity in good standing.

South Dakota EIN Frequently Asked Questions

These are the questions South Dakota LLC owners ask most about EINs and the state’s tax accounts. Short, decisive answers follow, with sources below.