South Dakota Tax ID Number: How to Register, File, and Pay

A South Dakota tax ID number is the license number the state Department of Revenue issues when you register for a Sales and Use Tax License. South Dakota has no personal or corporate income tax, so this sales tax license is the state-level registration most businesses need. The application is free, and you must have the license before your first taxable sale in the state.

Who Needs to Register

Two situations create the requirement. The first is physical presence: an office, warehouse, storefront, or employees located in South Dakota. Any business with a physical footprint in the state must be licensed for sales tax collection.

The second is economic nexus for remote sellers. Since the Supreme Court’s 2018 decision in South Dakota v. Wayfair, Inc., out-of-state businesses must register once their gross sales into South Dakota exceed $100,000 in the previous or current calendar year. South Dakota originally paired this with a 200-transaction trigger, but that alternative has been dropped; only the dollar threshold applies. The governing statute is South Dakota Codified Laws Chapter 10-64.¹

Gross sales for this test include tangible products, electronically delivered products, rentals, leases, and taxable services shipped or provided into the state. Where your warehouse sits doesn’t matter.

Get Your Federal EIN First

You’ll usually need a Federal Employer Identification Number from the IRS before applying to the state. Partnerships, LLCs, corporations, and any business with employees must have one. A sole proprietor with no employees can use a Social Security number instead, though many still choose an EIN to keep personal and business finances separate.

The fastest route is the online application at IRS.gov/EIN. If the responsible party has a valid Social Security number or ITIN, the system issues the EIN immediately. Fax takes about four business days; mail takes four to five weeks. The IRS limits issuance to one EIN per responsible party per day.²

Two details catch people off guard. If a sole proprietorship later incorporates or forms a partnership, you need a new EIN; the old number doesn’t carry over. And if the responsible party changes, you must file Form 8822-B with the IRS within 60 days.²

How to Apply for the South Dakota Tax License

Apply through the Department of Revenue’s online tax license application portal.³ This is a separate system from EPath, which you’ll use later for filing and payment. Have the following ready before you start:

Your EIN, or Social Security number if you’re a sole proprietor without one, matching what’s on file with the IRS.
Your legal business name, exactly as filed with the Secretary of State or the IRS.
Your six-digit NAICS code for your primary business activity. The Census Bureau’s NAICS search tool will help if you don’t know yours.
Your business start date, meaning the date you first make a sale or provide a taxable service in South Dakota.
Your ownership structure: sole proprietorship, partnership, LLC, corporation, or other.

There is no fee. A paper version can be printed from the Department of Revenue website and mailed to Pierre, but the online route is faster. Most applicants receive their license information within one to two weeks.

Filing and Paying After You’re Licensed

Once your license is active, the Department of Revenue assigns a filing frequency of monthly, quarterly, or annually based on the tax volume you’re expected to collect. The state sales and use tax rate is 4.2%, and municipalities may add up to 2% general municipal sales tax plus, in some cases, a 1% municipal gross receipts tax, so most cities land near 6.2%.⁴⁵ Use tax applies at the same rate on items brought into the state without correct sales tax charged. Your license covers both.

Whatever your frequency, the return is due by the 20th of the month after the reporting period ends. A January return is due February 20.⁶ Filing and payment run through the EPath portal, which also handles contractor’s excise tax and several other state taxes.⁷

The single most common compliance mistake: skipping a period because you had no sales. You must file a return every period whether or not you owe anything. Missing a zero-dollar return still triggers a penalty.⁸

Penalties for Late Filing or Payment

Returns filed more than 30 days late carry a penalty of 10% of the tax due or $10, whichever is greater.⁹ The $10 floor is why even zero-dollar returns need to be filed on time.

Late payments carry separate interest. For the first month, interest is 1% of the unpaid tax or $5, whichever is greater, and 1% per month accrues on the outstanding balance after that. If the Department of Revenue finds you intentionally avoided or delayed payment, the monthly rate is 1.5% or $5, whichever is greater.⁹

The Secretary of Revenue can reduce or eliminate penalties for reasonable cause. If the delinquency resulted from a genuine mistake about what the law required rather than an attempt to dodge tax, the secretary can also cap total interest at 24%.⁹

Other State Licenses That May Apply Alongside It

The sales tax license doesn’t cover every state tax obligation. Two categories often catch new businesses:

If you construct, install, or repair anything attached to real property, you need a separate contractor’s excise tax license. South Dakota imposes a 2% excise tax on gross receipts from construction projects. Prime contractors owe it on their full gross receipts; subcontractors generally don’t owe it if they have an exemption certificate from the prime, though subcontractors on qualified utility projects owe it on their own receipts. A speculative builder, meaning someone who buys land and builds on it intending to sell, is treated as a prime contractor and needs this license even when hiring the actual construction work out.¹⁰

Hospitality and recreation businesses owe an additional 1.5% tourism tax on top of regular sales tax. Hotels, campgrounds, car rental companies, recreational equipment rentals, spectator events, and visitor attractions all fall under it. A “visitor-intensive” business, one earning 50% or more of its annual revenue from June through September, owes the tourism tax only during those summer months.¹¹

If You Sell Into Multiple States

The Streamlined Sales Tax Registration System is a free, centralized way to register for sales tax in every participating state through one application. South Dakota is a full member.¹²

Streamlined handles registration only. You still file returns and pay tax through each state’s own portal at the frequency that state assigns, and you must file in every state where you’re registered, including periods with no sales.¹² If you’re already registered directly with South Dakota, you can join Streamlined and link your existing account rather than creating a duplicate.

Sellers who register through Streamlined can also contract with a Certified Service Provider for tax calculation and filing. For qualifying sellers, the provider’s compensation is paid by the states, so there’s no direct cost to the business.¹³

1
South Dakota Department of Revenue. Remote Seller Bulletin
2
Internal Revenue Service. Instructions for Form SS-4
3
South Dakota Department of Revenue. Tax License Applications
4
South Dakota Department of Revenue. Sales and Use Tax
5
South Dakota Department of Revenue. Municipal Tax
6
South Dakota Department of Revenue. Sales and Use Tax Laws and Regulations
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South Dakota Department of Revenue. Filing and Paying Taxes Online Help
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South Dakota Department of Revenue. Business FAQs
9
South Dakota Legislature. South Dakota Codified Laws 10-59-6
10
South Dakota Department of Revenue. Contractor’s Excise Tax
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South Dakota Department of Revenue. Tourism Tax
12
Streamlined Sales Tax. Streamlined Sales Tax Registration System
13
Streamlined Sales Tax Governing Board. Registration FAQ