LLC taxed as S corp vs S corporation in Idaho: which costs less (2026)

At $100,000 profit in Idaho, an LLC taxed as an S corp costs $21,383 a year in tax and fees and an S corporation costs $21,383. On these figures an S corporation does not cost less at any profit up to $500,000.

+$0 a year

more for an S corporation than an LLC taxed as an S corp in Idaho, at these numbers.

With these settings the switch does not pay at any profit from $10,000 to $500,000. As an S corporation this uses the state's pass-through entity tax election, which lowers the cost here.

Idaho, 2026: $100,000 profit, single filer

Item	LLC as S corp	S corp	Change
Payroll tax on your salaryirs.gov, 2026 rates	$6,562	$6,562	$0
Payroll service and tax return (estimate)	$1,800	$1,800	$0
Idaho permanent building fund taxtax.idaho.gov, checked Oct 23, 2026	$10	$10	$0
Idaho S corporation minimum taxtax.idaho.gov, checked Oct 23, 2026	$20	$20	$0
Idaho pass-through entity tax, paid by the company (elected)tax.thomsonreuters.com, checked Oct 23, 2026	$2,897	$2,897	$0
Federal income taxirs.gov, 2026 rates	$9,082	$9,082	$0
State income tax, after the PTET creditlegislature.idaho.gov, checked Oct 23, 2026	$1,012	$1,012	$0
Yearly cost	$21,383	$21,383	+$0

What these figures count

State income tax, and state taxes on the business itself: franchise, LLC, S corp, gross receipts and excise taxes.
Social Security and Medicare on both sides of an owner salary, federal unemployment tax and the state's new-employer rate.
The 20% qualified business income deduction with its income limits and the professional-service rule.
Yearly report fees, and a cost you can change for payroll and the business tax return.

Many S corp calculators leave out state taxes and the QBI deduction, which can make the election look better than it is.

Yearly cost at each profit level

Profit	LLC as S corp	S corp	Difference
$30,000	$7,002	$7,002	+$0
$50,000	$10,899	$10,899	+$0
$75,000	$14,497	$14,497	+$0
$100,000	$21,383	$21,383	+$0
$150,000	$36,321	$36,321	+$0
$200,000	$51,927	$51,927	+$0
$300,000	$85,511	$85,511	+$0

Federal and Idaho tax and fees, single filer, revenue 1.5 times profit, default salary for S and C corps. "Difference" is S corporation minus LLC taxed as an S corp.

What the switch takes in Idaho

File the Articles of Incorporation with the state: $100 (fee).
Federal return each year: Form 1120-S, due March 15, plus your own Form 1040.
State upkeep each year: Annual Report, no fee, due End of the anniversary month of incorporation.

What changes between the two

Both are taxed the same way by the IRS once the election is made: salary with payroll tax, the rest as a distribution, one Form 1120-S. The difference is state law: an LLC files Certificate of Organization and Annual Report, no fee, a corporation files Articles of Incorporation and Annual Report, no fee.

A corporation also has formalities an LLC skips: a board, bylaws, share records and yearly minutes. Most one-person businesses pick the LLC route for that reason.

Questions

How much does it save at $100,000 in Idaho?

Nothing. S corporation costs $0 a year more ($21,383 against $21,383).

Is an LLC taxed as an S corp the same as an S corp?

For federal tax, yes. For Idaho fees and paperwork, no: the LLC pays Annual Report, no fee and the corporation Annual Report, no fee.

More for Idaho

Common cases in Idaho

Other states