Unlike a few of its neighbors, Idaho does require an annual report from every LLC — but filing it costs nothing. Pair that with a reasonable formation fee and a flat income tax, and Idaho ends up being one of the cheaper states to actually keep a business running in year after year. Below is the full rundown for starting one in 2026.
1. Which business structure fits you?
Idaho founders typically pick from four structures, and the choice usually comes down to how much liability exposure you're willing to accept.
- Sole proprietorship. No paperwork needed to start, since you and the business are legally identical — which also means every debt the business runs up lands on you personally.
- Partnership. Two or more people sharing a business, and sharing the same liability exposure a sole proprietor would carry alone.
- LLC. The typical choice for small Idaho businesses, mainly for the wall it puts between your personal assets and the company's debts or lawsuits.
- Corporation, S-corp or C-corp. Involves more formality and paperwork, and tends to make sense once you bring on investors or multiple shareholders.
See our business structure comparison for a fuller breakdown.
LLCs and corporations register with Idaho Secretary of State, Business Services, which handles business filings statewide. Sole proprietorships and general partnerships have no reason to register there.
2. Register your business
Forming an LLC
A Certificate of Organization filed with the Secretary of State is what forms your Idaho LLC. It costs $100 online or $120 by mail, and online filings usually process within 3 to 5 business days.
Idaho LLCs also need a registered agent at a physical Idaho address, available during business hours — you can serve in that role yourself or pay a commercial service.
There's no legal requirement in Idaho to have an operating agreement, but writing one is still a good idea, particularly with more than one member, since it lays out how decisions and profits actually get divided.
Sole proprietorships and DBAs
No Certificate of Organization gets filed for a sole proprietorship. Operating under an assumed business name means registering that name directly with the Secretary of State instead.
3. Get an EIN
The IRS hands out an Employer Identification Number for free, and the online application usually takes about 15 minutes. Whether you're hiring your first employee, opening a business bank account, or filing most business tax forms, you'll need one — even as a single-member LLC with no staff.
4. Check licenses and permits
No single statewide business license applies to everyone in Idaho. What you actually need depends on your industry and city: regulated professions go through the Division of Occupational and Professional Licenses, and selling taxable goods means getting a seller's permit from the State Tax Commission. Our guides on professional licensing by industry and zoning laws for home businesses go into more detail.
5. Understand Idaho taxes
Idaho taxes personal income at a flat 5.3%. Pass-through LLCs don't owe any separate franchise tax, and electing corporate treatment brings the same 5.3% rate applied at the corporate level instead.
Statewide sales tax sits at a flat 6%. A handful of tourism towns — Sun Valley, McCall, and Stanley among them — add a local option Resort City Tax of up to 3% on top, but most of the state has no local add-on whatsoever.
6. Stay compliant
Idaho LLCs file an Annual Report with the Secretary of State by the last day of their anniversary month each year. Filing it online is free; a paper filing runs $20. Charging nothing for a mandatory state filing is unusual, but Idaho does it — you still need to file on time, though, or risk administrative dissolution.
Idaho business costs at a glance
| Item | Cost |
|---|---|
| Certificate of Organization (LLC) | $100 online / $120 mail |
| Annual Report (every year) | Free online / $20 paper |
| Registered agent service (optional) | $39 to $150/year |
| EIN | Free (IRS) |
| State income tax | 5.3% flat |
| State sales tax | 6% flat (+3% resort city tax in a few towns) |
Frequently asked questions
Does Idaho charge for its annual LLC report?
Not if you file online — that's free. A paper filing costs $20, which is unusual for a filing the state actually requires.
How much does it cost to form an LLC in Idaho?
A Certificate of Organization runs $100 online or $120 by mail.
What's the personal income tax rate in Idaho?
A flat 5.3% across the board.
Is sales tax the same everywhere in Idaho?
Nearly. The statewide rate is a flat 6%, though towns like Sun Valley, McCall, and Stanley tack on a Resort City Tax of up to 3%.
When is Idaho's Annual Report due?
By the last day of whatever month your LLC was formed in, every year.
Fees and rates above come from the Idaho Secretary of State and State Tax Commission as of 2026, and they do change over time, so double check before you file. None of this is legal or tax advice. Talk to an Idaho-licensed attorney or CPA about your specific situation.