StructureCost2026

LLC or S corp for a physician in Idaho (2026)

A physician in Idaho with $270,000 of profit pays $91,676 a year in tax and fees as a sole proprietor and $92,192 as an LLC taxed as an S corp, with a $189,000 salary. The S corp starts to pay at about $275,000 of profit.

More settings revenue, salary, filing status, payroll costs, PTET

+$516 a year

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

Switching from a sole proprietorship to an LLC taxed as an S corp starts to pay at about $275,000 of profit, with the same settings. Setting up costs $100 once in state filing fees. As an LLC taxed as an S corp this uses the state's pass-through entity tax election, which lowers the cost here.

Idaho, 2026: $270,000 profit, single filer

ItemSole propLLC as S corpChange
Self-employment taxirs.gov, 2026 rates$30,553$0−$30,553
Federal income taxirs.gov, 2026 rates$48,719$49,058+$339
State income tax, after the PTET creditlegislature.idaho.gov, checked Oct 23, 2026$12,404$8,909−$3,495
Payroll tax on your salaryirs.gov, 2026 rates$0$28,984+$28,984
Payroll service and tax return (estimate)$0$1,800+$1,800
Idaho permanent building fund taxtax.idaho.gov, checked Oct 23, 2026$0$10+$10
Idaho S corporation minimum taxtax.idaho.gov, checked Oct 23, 2026$0$20+$20
Idaho pass-through entity tax, paid by the company (elected)tax.thomsonreuters.com, checked Oct 23, 2026$0$3,411+$3,411
Yearly cost$91,676$92,192+$516
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.

At three profit levels

ProfitSalary usedSole propLLCLLC as S corpC corp
$180,000$126,000$54,816$54,816$56,118$63,302
$270,000$189,000$91,676$91,676$92,192$101,319
$390,000$244,000$146,343$146,343$142,591$149,418

Salary is the BLS median for the job ($244,180), capped at 70% of profit. Revenue 2 times profit. Single filer.

What matters for physicians

What the switch takes in Idaho

  1. File the Certificate of Organization with the state: $100 (fee).
  2. Get an EIN from the IRS (free, online) and open a business bank account in the new name.
  3. Check the business can elect: no more than 100 shareholders, all of them US citizens or residents (no nonresident alien owners), and one class of stock. IRS
  4. File IRS Form 2553 to elect S corp tax treatment, within 2 months and 15 days of the start of the tax year it should apply to. See how the S corp election works.
  5. Register with Idaho as an employer and run payroll for your own salary: federal Forms 941 each quarter, Form 940 and a W-2 each year. New employers pay Idaho unemployment tax at 1% on the first $58,300 of wages. labor.idaho.gov See what payroll costs.
  6. Federal return each year: Form 1120-S, due March 15, plus your own Form 1040.
  7. State upkeep each year: Annual Report, no fee, due End of the anniversary month of formation. New for you: Idaho permanent building fund tax, Idaho S corporation minimum tax.

Questions

Should a physician in Idaho form an S corp?

At $270,000 of profit, not on these figures: the S corp costs $516 a year more than staying a sole proprietor.

Is an LLC worth it for a physician in Idaho?

For tax, a single-member LLC changes nothing: $91,676 a year against $91,676, the difference being Idaho's LLC fees. It separates business liability and is the base for an S corp election.

More

Other professions in Idaho
Other states