No personal income tax
South Dakota doesn't have a corporate, unitary, or personal income tax, so your quarterly payments go to the IRS.
South Dakota tax guide
South Dakota taxes for self-employed workers in 2026
South Dakota has no personal income tax, but the taxes on contractors and some services catch people out.
Published by Cadus Labs LLC · Last updated November 9, 2026 · How we write these guides
Based on the South Dakota DOR's 2026 sales and use tax guide and other official state guidance.
Contractors and service businesses
Prime contractors doing construction or realty improvement work owe a 2% contractor's excise tax on gross receipts. There's no fee for the license, and you need one regardless of how much you receive.
Some services are subject to sales tax instead. For example, lawn, garden, and tree services are taxable when they're done apart from a contract for realty improvements.
Your federal tax comes first
Wherever you live, self-employed income is subject to federal income tax and self-employment tax. A single filer with $60,000 of net profit and no other income owes about $12,037 in federal tax for 2026, or 20% of profit, before any state or local tax.
Federal estimated payments are due April 15, June 15, and September 15, 2026, and January 15, 2027. Use our 1099 tax calculator to run your own numbers.
Recordkeeping checklist
Set aside for federal tax from every payment you receive.
Make federal estimated payments if you expect to owe enough.
Keep receipts and a mileage log for everything you deduct.
Check whether your work needs a South Dakota sales or excise tax license.
Free tools for this
Calculator
1099 and Self-Employment Tax Calculator
Enter your 1099 income and business expenses to estimate self-employment tax, federal income tax, and what to set aside each quarter. No sign-up, and nothing you type is saved.
Calculator
Quarterly Tax Set-Aside Calculator
Turn expected profit into a practical tax savings target, then use Cadus to keep income, expenses, deductions, receipts, and reports organized.
Template
Quarterly Tax Savings Worksheet
Use this worksheet to turn expected monthly profit into a practical tax savings target before estimated tax due dates arrive.
Template
Business Expense Log Template
Copy this table to start organizing business purchases, receipt proof, categories, and business purpose before moving records into Cadus.
Official sources
Related guides
Self-employment tax guide
Self-Employment Tax
The self-employment tax rate is 15.3%. See who pays, how the 2026 wage base works, the deduction for half the tax, and a worked example.
Estimated tax guide
Quarterly Estimated Taxes
2026 estimated tax due dates, who has to pay, how to avoid the penalty, and a worked example for a self-employed worker earning $60,000.
Schedule C education
Schedule C Expense Categories
Every Schedule C expense line in plain English: what goes on each one, what doesn't, and the records to keep for self-employed workers.
South Dakota Taxes FAQ
Is there a state income tax in South Dakota?
No. You still owe federal income tax and self-employment tax.
What is South Dakota's contractor's excise tax?
A 2% tax on the gross receipts of prime contractors doing construction or realty improvement work.
Cadus educational content is not tax, legal, or accounting advice. Tax rules can change, and individual facts matter. Review official guidance or speak with a qualified tax professional before filing.