The S-Corp Election Window Closes March 15: How To Time It From Q4

Updated: August 2026 · Industry Advisors · Education, not legal or tax advice.

The S-Corp election has one hard deadline that catches founders every year: March 15. To have S-Corp status apply to a given tax year, Form 2553 must be filed by the 15th day of the third month of that year. Filed later, it applies to the following year.

But the decision itself should not be made in March. By then, everything the election requires — a reasonable-salary calculation, payroll registration, a bookkeeping upgrade, and often a new bank account — is already crunched into a two-week fire drill. The right time to decide is November, four months earlier, when the runway is clean.

Here is what the S-Corp election actually does, when it is worth it, and the Q4 workflow to time it right.

What "S-Corp" Actually Means

S-Corp is not an entity type. It is a tax election that an LLC or corporation can make on Form 2553 with the IRS. The underlying entity — an LLC or a state-formed corporation — stays exactly the same. What changes is how the IRS taxes the profits.

Default LLC tax treatment (single-member):

• Profit flows through to your personal Schedule C.
• You pay federal income tax on the full profit.
• You also pay self-employment tax (15.3% — Social Security + Medicare) on the full profit, up to the wage base.

S-Corp election (single-member LLC that elects S-Corp):

• You become an employee of your own LLC. You pay yourself a "reasonable salary" via payroll.
• The salary is subject to payroll tax (functionally the same 15.3% split employer/employee).
• The remaining profit is paid to you as a distribution and is not subject to self-employment tax.
• Federal income tax still applies to both the salary and the distribution.

The tax saving comes entirely from that second bullet: the portion of profit paid as distribution avoids self-employment tax. On a well-structured election, the annualized saving is roughly 7.65% of the distribution.

The Break-Even Math

The election only makes sense once the tax saving exceeds the added compliance cost. Compliance cost includes:

• Payroll service, typically $40–$70/month ($480–$840/year)
• Higher tax-prep fee — Form 1120-S plus K-1 typically runs $800–$1,800 vs. Schedule C at $200–$500
• State-level franchise or S-Corp-specific taxes (California charges 1.5% on S-Corp net income with an $800 floor; New York City has a similar surtax)

Rough break-even guide (federal only, before state):

Estimates only. Your numbers vary with reasonable-salary level, state, and structure. Confirm with a licensed CPA.

What "Reasonable Salary" Actually Means

This is the piece the IRS actually audits. Setting your salary too low to avoid payroll tax is the number-one S-Corp red flag. The IRS test is straightforward: what would you pay someone else to do your job at market rate?

The most defensible approaches:

• Look up the median wage for your role in your metro on the Bureau of Labor Statistics Occupational Employment and Wage Statistics tables.
• Take the 60-40 rule as a starting sanity check: roughly 60% of net profit as salary, 40% as distribution — then adjust to whichever floor is higher.
• Document the calculation in a memo saved with your Operating Agreement. If audited, the memo is the first thing the examiner asks to see.

The Q4 Workflow

If you have decided the election is worth it, this is the four-month runway to March 15:

November

• Run the break-even math against year-to-date profit.
• Talk to a CPA who has done at least a dozen S-Corp elections in the last 12 months.
• Decide on the target reasonable salary and document the reasoning.

December

• Set up a payroll service. Most providers can enroll and register with the state in 1–3 weeks.
• Register with the state for employer withholding and unemployment insurance.
• Confirm the LLC has a separate business bank account. Distributions must be traceable.

January

• Run the first payroll on the salary you set. Even one small January run establishes the pattern.
• Prepare Form 2553. It is one page. Confirm every member has signed.

By March 15

• File Form 2553 with the IRS by fax or certified mail. Save the fax confirmation or certified receipt.
• Wait 60 days for the IRS acceptance letter (CP261). Store with corporate records.

Late-Election Relief

Missed March 15? Rev. Proc. 2013-30 allows late elections up to three years and 75 days after the intended effective date, provided you had reasonable cause and have been operating as if the election were in effect. It works. It is not a plan.

When The Election Is The Wrong Answer

The S-Corp election has real costs beyond dollars:

• Passive-income restrictions. An S-Corp with more than 25% passive income for three consecutive years can lose the election.
• Single class of stock. No dual-class equity, which rules out most VC-backed rounds.
• Ownership limits. No more than 100 shareholders. No non-resident aliens. No corporate or partnership owners.
• Retirement-plan reset. Solo 401(k) contribution limits shift because they are calculated on salary, not net profit.

If any of these will be true in the next 24 months, staying with default LLC treatment or planning toward a C-Corp conversion is often the better path.

The One-Line Summary

Decide in November. Set up payroll and bank accounts in December. Run the first paycheck in January. File Form 2553 by March 15. Do not make this decision in March.

The Everyday Owner's Blueprint includes the S-Corp break-even worksheet, a reasonable-salary calculator, and a completed sample Form 2553 alongside the full 12-week formation and compliance walk-through.

Industry Advisors · 30 Wall Street, New York, NY 10005. Education, not legal or tax advice. Confirm your election strategy with a licensed CPA before you file.