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

At $100,000 profit in Montana, an LLC taxed as an S corp costs $21,491 a year in tax and fees and an S corporation costs $21,491. 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 Montana, 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.

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

Item	LLC as S corp	S corp	Change
Payroll tax on your salaryirs.gov, 2026 rates	$6,674	$6,674	$0
Payroll service and tax return (estimate)	$1,800	$1,800	$0
Montana pass-through entity tax, paid by the company (elected)news.bloombergtax.com, checked Oct 23, 2026	$3,084	$3,084	$0
Federal income taxirs.gov, 2026 rates	$9,034	$9,034	$0
State income tax, after the PTET creditrevenue.mt.gov, checked Oct 23, 2026	$899	$899	$0
Yearly cost	$21,491	$21,491	+$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	$7,229	$7,229	+$0
$50,000	$11,019	$11,019	+$0
$75,000	$14,523	$14,523	+$0
$100,000	$21,491	$21,491	+$0
$150,000	$36,506	$36,506	+$0
$200,000	$52,262	$52,262	+$0
$300,000	$86,111	$86,111	+$0

Federal and Montana 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 Montana

File the Articles of Incorporation (Profit Corporation) with the state: $35 (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 April 15.

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 Articles of Organization and Annual Report, no fee, a corporation files Articles of Incorporation (Profit Corporation) 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 Montana?

Nothing. S corporation costs $0 a year more ($21,491 against $21,491).

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

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

More for Montana

Common cases in Montana

Other states