Ten S-Corp Mistakes That Create Tax Problems (and How to Prevent Them)

The S-corp structure rewards discipline and punishes drift. None of the mistakes below require bad intent, and most can be fixed if caught early. They are listed roughly in the order in which we would expect an examiner or a new adviser to find them.

1. Electing S status and never running payroll

The election is only half the job. An owner who performs services must be paid wages, so a company that elects and then continues taking draws is out of compliance from the first month. The fix is to start payroll immediately and to address prior periods with a professional. See S-corp payroll for owner-employees.

2. Paying an unreasonably low salary

A very low salary paired with large distributions is the classic audit trigger. Price the work, document it, and revisit annually. See reasonable compensation and setting your owner salary.

3. Taking non-proportional distributions

If one shareholder takes money and others do not, or amounts differ from ownership percentages, you have a problem to correct. Even when the election survives, the situation can generate compensation, loan, or gift questions. Keep distributions pro rata or document and cure the difference. See S-corp distributions explained.

4. Not tracking shareholder basis

Owners deduct losses they cannot use or take distributions that exceed basis without recognizing the gain. Both errors are avoidable with a simple annual schedule. See S-corp shareholder basis.

5. Mishandling health insurance and other fringe benefits

Premiums for more-than-2-percent shareholders need to be on the W-2, and other fringe benefits are subject to special rules. See health insurance for S-corp owners.

6. Holding real estate inside the S-corp

Real estate often appreciates, and getting it out of an S-corp can trigger gain at the corporate level that passes to shareholders. Real estate held inside a corporate structure also limits certain planning options like basis step-ups and flexible allocations available in partnerships. Many advisers prefer a separate LLC to hold real estate and lease it to the operating company. See owning your building in a separate LLC.

7. Commingling funds and skipping formalities

An S-corp is still a corporation or an LLC, and courts treat commingling as evidence of alter ego. Use a separate bank account, avoid paying personal bills from the company, and keep basic records such as minutes and written consents where required. See separating personal and business finances and piercing the corporate veil.

8. Late or missing returns and payroll filings

Form 1120-S carries penalties per shareholder per month for lateness, and payroll returns carry their own penalties. Extensions are available for the income tax return, but not for payroll deposits. Put every date in a calendar. See small business tax calendar.

9. Ignoring state rules

Some states do not recognize S status, require separate elections, or tax S-corps at the entity level. Others have franchise taxes or minimum fees. Owners who move or expand into new states can pick up nexus and filing duties without noticing. See state income tax and remote employees and pass-through entity tax.

10. Accidentally creating a second class of stock

Operating agreements with preferred returns, disproportionate distribution rights, or unusual loan terms can create problems. Review governing documents when the S election is made and again when anything changes. See S-corp eligibility rules.

Bonus mistakes worth knowing

• Assuming an "Inc." is an S-corp. The default for a corporation is C status until an election is made and accepted.
• Ignoring the accepted election letter. Some businesses discover, years later, that the IRS never accepted the form because of an error.
• Mixing expense reimbursements and distributions. An accountable plan keeps reimbursements clean.
• Deducting personal expenses. These are recharacterized as compensation or distributions in an exam.
• Not updating records when an owner is added or removed. See adding or removing an owner.
• Failing to reconcile payroll to the return. Wages on the 941s, W-2s, and the 1120-S should agree.

A monthly routine

1. Reconcile bank and credit card accounts.
2. Confirm payroll ran and taxes were deposited.
3. Review the balance sheet for owner-related accounts: loans, distributions, and payroll liabilities.
4. Move any personal transactions into the right accounts.
5. Scan for large or unusual items to categorize properly.

Building that habit is easier with a monthly close checklist. See month-end close checklist.

A yearly routine

1. Review the salary against market and profit.
2. Project profit and estimate taxes. See estimated taxes guide.
3. Update basis schedules.
4. Confirm fringe benefit reporting.
5. Review the operating agreement or bylaws for S-compatibility.
6. Confirm state filings and fees are current.
7. Calendar the 1120-S, K-1s, and payroll year-end deadlines.

When problems already exist

If you see yourself in a few of these, the sensible response is inventory first. List what happened, what years are affected, and what the records show. Then decide what to fix and how. Options may include filing amended returns, running catch-up payroll, documenting loans, correcting distributions, or seeking late election relief. Some are simple and some are not. Review the entity cleanup guide to see how a structured review works.

A closing thought

The S-corp works best when it feels boring: payroll runs, distributions follow the plan, books close monthly, and the return matches the records. If yours does not feel boring yet, AE Tax Advisors can help you get there, and you can start with a discovery call.