The main disadvantages of an S corporation are strict ownership and stock rules that are easy to violate, income and loss allocations locked to share ownership, IRS scrutiny of owner salaries, taxable treatment of fringe benefits for owners, conversion-related taxes for former C corporations, uneven state recognition, and the payroll and filing overhead of running a corporate entity. Any one of these can shrink or erase the tax savings the election was meant to produce.
Eligibility Rules That Can End the Election Overnight
S corporation status depends on continuously satisfying a narrow set of IRS rules. Break one, even inadvertently, and the election terminates as of the date of the violation, dropping the corporation back to C status. Once terminated, the corporation generally must wait five tax years before re-electing. The IRS can grant relief for inadvertent terminations through a formal ruling request, but approval is not guaranteed.
Three rules do most of the damage:
- The corporation can never have more than 100 shareholders. Family members can be counted as one under certain rules, but the ceiling blocks broad equity raises and crowdfunding-style capital strategies.
- Only individuals, estates, and certain trusts may hold stock. Partnerships, other corporations, and non-resident aliens are all excluded, which alone can foreclose international investment.
- All outstanding shares must carry identical rights to distributions and liquidation proceeds. Voting rights can differ, but the corporation cannot issue preferred stock with priority dividends or liquidation preferences.
The single-class-of-stock rule is especially painful for growth companies. Venture capital and angel investors routinely demand preferred shares with liquidation preferences, anti-dilution protections, or guaranteed dividends. An S corporation cannot offer any of those without blowing its election.
Income and Losses Have to Follow Ownership Percentages
Partnerships can split income and losses among owners in almost any way the partners negotiate. S corporations cannot. Every item of income, loss, deduction, and credit is allocated to shareholders strictly in proportion to stock ownership.
This becomes a real problem when owners contribute unequal amounts of capital or labor. If one shareholder put up 80% of the startup money but holds 50% of the stock, that shareholder’s share of taxable income is still 50%. There is no mechanism for a special allocation that reflects economic reality.
Losses Don’t Automatically Become Deductions
Even when an S corporation generates large losses, shareholders may not be able to deduct them. Losses pass through on paper, but the tax code imposes a series of limitations each shareholder must clear.
The first is the basis limitation. A shareholder can deduct losses only up to the combined total of stock basis and any debt the corporation owes directly to that shareholder. Unlike a partnership, where a partner’s basis increases when the entity borrows from a bank, an S corporation’s outside loans do not increase any shareholder’s basis. A business financing growth with bank debt can generate losses its owners cannot use. Losses beyond basis are not gone; they suspend and carry forward until the shareholder has enough basis to absorb them.
Losses that clear the basis hurdle then have to survive the at-risk rules and the passive activity rules. The at-risk rules limit deductions to amounts the shareholder has personally at risk in the activity. The passive activity rules disallow losses from a business in which the shareholder does not materially participate, suspending them until the shareholder either materially participates or disposes of the interest entirely.
Owner Salaries Are Under IRS Scrutiny
Every shareholder who performs services for the corporation must be paid a reasonable salary before taking any distributions. Salary is subject to FICA (6.2% Social Security plus 1.45% Medicare from both the employee and employer); distributions generally are not. The temptation to minimize salary and maximize distributions is obvious, and the IRS knows it.
Reasonableness is judged on factors like the shareholder’s training and experience, duties and responsibilities, time devoted to the business, what comparable businesses pay for similar services, and the corporation’s dividend history relative to compensation. There is no safe harbor or bright-line dollar threshold.
Getting it wrong is expensive. If the IRS reclassifies distributions as wages, the corporation owes back employment taxes on the reclassified amount, plus penalties and interest. The employer’s share alone adds 7.65% on wages up to the $184,500 Social Security wage base in 2026, and 1.45% above that. An additional 0.9% Medicare tax applies to employee wages exceeding $200,000 for single filers. Accuracy-related penalties and late-deposit penalties can stack on top.
Reasonable Salary Shrinks the QBI Deduction
Reasonable compensation paid to a shareholder-employee is excluded from qualified business income. Every dollar classified as salary shrinks the base on which the Section 199A 20% deduction is calculated.
Take an S corporation earning $300,000. If the owner takes $100,000 as salary, only $200,000 qualifies as QBI, producing a maximum deduction of $40,000. A sole proprietor or single-member LLC earning the same $300,000 could calculate the deduction on the full amount, potentially yielding $60,000 (subject to other limitations). The payroll tax savings on distributions can be partially or fully offset by the reduced QBI deduction, and many owners never run the comparison.
For owners of specified service trades or businesses (law, medicine, consulting, accounting), the problem compounds. Once taxable income crosses $201,750 for single filers or $403,500 for joint filers in 2026, the QBI deduction begins phasing out. At higher income levels these owners may get no QBI deduction at all, leaving the reasonable salary requirement as a pure cost.
Fringe Benefits Are Taxable for Owners
Any shareholder owning more than 2% of the corporation’s stock is treated like a partner in a partnership for fringe benefit purposes. Benefits that would be tax-free for regular employees become taxable income for these owners.
Health insurance is the clearest example. When the S corporation pays health premiums for a more-than-2% shareholder, the premium is included in the shareholder’s W-2 as taxable wages. The shareholder can then claim an above-the-line deduction for self-employed health insurance on the personal return, but only if specific eligibility requirements are met. A C corporation simply deducts the cost and the employee-owner receives the benefit entirely tax-free.
The same treatment applies to group-term life insurance above $50,000 in coverage, employer-provided meals and lodging, and qualified small employer health reimbursement arrangements. More-than-2% shareholders cannot participate in a QSEHRA at all.
Conversion From a C Corporation Carries Its Own Taxes
Converting a C corporation to S status does not wipe the slate clean. Appreciation that built up under C status follows the company into its S years.
Any asset worth more than its tax basis on the date the S election takes effect carries a “built-in gain.” Selling that asset within a five-year recognition period triggers the built-in gains tax at 21% at the corporate level under Section 11(b). The remaining gain then passes through to shareholders and is taxed again on their individual returns. That is exactly the double taxation the S election is supposed to avoid, and during the recognition period it applies in full.
A conversion analysis needs to inventory every appreciated asset (real estate, equipment, goodwill, receivables for cash-basis taxpayers) and ask whether the business can hold each one for the full five years. A single early sale can generate a tax bill that dwarfs the year’s pass-through savings.
LIFO Recapture
C corporations using last-in, first-out inventory owe an additional conversion cost. The entire LIFO reserve, meaning the difference between LIFO and FIFO inventory values, must be included in gross income on the final C corporation return. The tax is paid in four equal annual installments starting with that return and continuing over the next three S corporation years. For companies with large LIFO reserves, the upfront hit can be substantial.
The Passive Investment Income Trap
S corporations that inherited accumulated earnings and profits from their C years face a separate risk. If more than 25% of gross receipts come from passive sources (interest, dividends, rents, royalties, annuities) while the corporation still holds accumulated E&P, the excess net passive income is taxed at 21% at the corporate level.
Worse, if the corporation crosses that 25% threshold for three consecutive years while still holding accumulated E&P, the S election terminates automatically at the start of the following year. The IRS can waive the penalty tax if the corporation shows a good-faith belief it had no accumulated E&P and distributes those earnings within a reasonable time after discovering them. Prevention is easier: distribute all accumulated E&P soon after conversion.
State Tax Treatment Doesn’t Always Match Federal
Federal pass-through treatment does not automatically follow at the state level. The District of Columbia and Tennessee have historically taxed S corporations the same as any other corporation. Texas applies its franchise tax regardless of federal S status. California charges a minimum franchise tax even in years with no income.
Other states recognize the S election but layer on separate entity-level taxes or minimum fees. Many have also adopted elective pass-through entity taxes as a workaround to the $10,000 federal cap on state and local tax deductions; these can help shareholders but add compliance work. The election can reduce federal taxes while doing little or nothing at the state level, so both sides need to be modeled before filing.
Payroll, Filings, and Penalties
Running an S corporation means running a payroll system. The corporation has to pay its owner-employees through formal payroll, withhold income tax and FICA, file quarterly payroll tax returns, issue W-2s at year end, and file Form 1120-S with a Schedule K-1 for every shareholder. A single-member LLC taxed as a disregarded entity or a sole proprietorship carries none of that.
Late or incomplete filings are costly. A late Form 1120-S triggers a penalty of $255 per shareholder per month (or partial month), up to 12 months. A five-shareholder S corporation filing three months late owes $3,825 in penalties alone. Annual report fees and state franchise taxes add to the carrying costs and vary widely by state.
None of these costs sinks the election on its own. For a smaller business where the payroll tax savings on distributions are modest, the combined overhead can eat into, or exceed, the benefit the election was chosen to deliver.