S Corporation Audit Procedures: What to Expect in 2026
If your S corporation receives an IRS examination notice, understanding what happens next can turn anxiety into confidence. The IRS examination process follows specific procedures designed to review particular compliance areas. Knowing these procedures, what examiners actually look for, and how to respond effectively helps you navigate the process
while protecting your business interests.
This guide explains S corporation audit procedures based on current IRS examination protocols and provides
practicalstrategies for preparation and response.
How the IRS Selects S Corporations for Examination
The IRS doesn’t randomly select returns for examination. According to IRS Internal Revenue Manual 4.1.5 (as updated January 2026), S corporation returns are identified through the Enterprise Case Selection (ECS) system, which replaces legacy manual classification with an AI-driven, risk-based modeling process.
The Classification Process: The IRS uses both automated systems and manual review to identify returns for examination.
Returns are classified based on:
- Specific compliance issues that historically result in tax adjustments
- Patterns suggesting employment tax avoidance
- Discrepancies in reported income or deductions
- Issues likely to require examination to increase voluntary compliance
Understanding this selection process reveals an important truth: S corporation status alone doesn’t increase audit risk. Under the IRS 2026 Strategic Operating Plan, the agency has specifically allocated funding to increase audit rates for S corporations and other complex pass-through entities, meaning these entities now face higher scrutiny than in previous years.
Types of IRS S Corporation Examinations
The IRS conducts S corporation examinations through different processes depending on the issues identified and the complexity involved.
| Examination Type | Description | Typical Issues Reviewed |
|---|---|---|
| Correspondence Examination | Conducted primarily through the IRS Taxpayer Portal and secure digital correspondence | Limited scope issues like specific deductions or credits |
| Office Examination | Conducted at the IRS office | More complex issues require detailed documentation |
| Field Examination | Conducted at the business location or the representative’s office | Comprehensive review of multiple tax years and complex issues |
Field examinations typically involve S corporations with more complex structures, multiple shareholders, or significant compliance concerns.
What IRS Examiners Actually Review
IRS examiners follow specific guidelines when examining S corporation returns. According to IRS Internal Revenue Manual (IRM) 4.1.5 (as updated January 2026), examiners utilize Enterprise Case Selection (ECS) protocols to identify specific high-risk compliance factors and multi-layer pass-through relationships.
Primary Examination Focus Areas
1. Reasonable Compensation for Shareholder-Employees
This remains the single most scrutinized area in S corporation examinations. The IRS examines whether shareholder-employees receive reasonable compensation for services performed, rather than improperly minimizing wages to avoid employment taxes.
Source: IRS Reasonable Compensation Job Aid for Valuation Professionals (This job aid provides the multi-factor test currently used by examiners to determine market-rate salary).
What examiners review:
- W-2 wages compared to distributions received
- Services performed by shareholder-employees
- Industry compensation benchmarks
- Business profitability and revenue
- Shareholder qualifications and experience
Examiners request documentation supporting how compensation was determined and compare it against industry standards.
2. Stock and Debt Basis Calculations
Examiners verify that shareholders properly calculate and track stock and debt basis. This directly impacts whether distributions are taxable and whether losses can be deducted.
Specific examination procedures:
| Basis Component | What Examiners Verify |
|---|---|
| Initial stock basis | Correct calculation of the basis at S election or stock acquisition |
| Annual adjustments | Proper ordering of increases and decreases |
| Debt basis | Documentation of actual loans to the corporation (not guarantees) |
| Loss limitations | Losses are only deducted to the extent of the available basis |
| Distribution treatment | Correct tax treatment based on the available basis |
Note: Under Treasury Regulation 1.1367-1(g), shareholders may elect to decrease basis by items of loss and deduction before decreasing basis by non-deductible, non-capital expenses.
Source: IRS S Corporation Stock and Debt Basis
According to IRS guidance, basis adjustments must follow specific ordering rules.
Examiners check whether the basis was:
- Increased for income items and excess depletion
- Decreased for distributions
- Decreased for non-deductible, non-capital expenses
- Decreased for items of loss and deduction
Failure to follow these ordering rules results in improper loss deductions or incorrect tax treatment of distributions.
Source: IRS S Corporation Stock and Debt Basis guidance; IRS Form 7203 Instructions – S Corporation Shareholder Stock and Debt Basis Limitations
3. Personal Expenses Paid by the Corporation
Examiners review whether the S corporation pays shareholders’ personal expenses and improperly treats them as corporate deductions rather than shareholder compensation or distributions.
Commonly examined personal expense categories:
- Vehicle expenses: Proper documentation of business vs. personal mileage
- Travel and entertainment: Business purpose substantiation and receipts
- Home office deductions: Exclusive and regular business use documentation
- Health insurance for >2% shareholders: Correct reporting in W-2 Box 1
- Family member payments: Whether compensation is reasonable for services actually performed
Source: IRS Fact Sheet FS-2008-25 – Wage Compensation for S Corporation Officers
4. Shareholder Loans and Related-Party Transactions
The IRS examines loans between S corporations and shareholders because they can easily become disguised compensation or distributions.
What triggers examiner scrutiny:
- Loans lacking written agreements or documentation
- Loans with no stated interest rate or below-market rates
- Shareholder “loans” that are never repaid
- Loan guarantees are incorrectly treated as creating a debt basis
- Examiners now strictly apply the ‘Actual Outlay’ doctrine, requiring verified documentation of the flow of funds directly from the shareholder’s personal accounts to the corporation to establish debt basis.
A shareholder only receives debt basis to the extent they personally lent money to the S corporation. Loan guarantees do not create a debt basis.
Source: IRS S Corporation Stock and Debt Basis guidance
5. S Election Eligibility and Ongoing Compliance
Examiners verify that the corporation continues to meet S election requirements:
- No more than 100 shareholders
- Only eligible shareholders (individuals, certain trusts, and estates)
- One class of stock
- Domestic corporation status
Source: IRS Form 1120-S Instructions
The S Corporation Examination Process Timeline
Understanding what happens at each stage helps you prepare appropriate responses and documentation.
Initial Contact and Information Document Request (IDR)
What happens:
| The IRS sends an examination notice identifying: | Your response obligations: |
|---|---|
| Tax years under examination | Verify the examination period and specific issues identified |
| Specific issues the examiner will review | Gather requested documentation |
| Initial documentation requested | Contact the examiner or authorize a representative |
| Examiner contact information | Request extension if additional time is needed to compile records |
| Response deadline (typically 30 days) |
Document Review and Examiner Analysis
What the examiner does:
- Reviews submitted documentation against tax return positions
- Analyzes reasonable compensation methodology
- Recalculates shareholder basis
- Examines expense substantiation and business purpose
- Compares reported amounts to industry benchmarks
- Identifies discrepancies or compliance issues
Additional information requests: Examiners typically submit follow-up Information Document Requests (IDRs) as they review initial documentation and identify additional questions.
Proposed Adjustments and Taxpayer Response
If the examiner identifies issues:
The examiner issues a proposed adjustment explaining:
- Specific tax issues identified
- Proposed changes to taxable income
- Reasoning and legal basis for adjustments
- Calculations of additional tax, interest, and potential penalties
Your response options:
| Response Option | When to Use | Next Steps |
|---|---|---|
| Agreement | Adjustments are correct, or the cost of disagreement exceeds the benefit | Sign the agreement form, pay the assessed amounts |
| Partial agreement | Some adjustments are correct, others are disputed | Agree to undisputed items, contest remaining issues |
| Complete disagreement | Adjustments are incorrect or unsupported | Submit a written protest and request an appeals conference |
Appeals Process
If you disagree with proposed adjustments, you can request an appeals conference with the IRS Office of Appeals. This provides an independent review before any assessment becomes final.
Appeals procedures:
- Submit a written protest within 30 days of the examination report
- Explain specific disagreements and supporting facts
- Provide a legal basis for your position
- Include supporting documentation not previously submitted
- Attend appeals conference (in person or by phone)
Appeals officers have the authority to reach settlement agreements based on the hazards of litigation for both parties.
Common Examination Outcomes and Adjustments
Understanding typical examination results helps you assess potential exposure and response strategies.
Most Common S Corporation Adjustments:
| Adjustment Type | IRS Action | Tax Impact |
|---|---|---|
| Reclassification of distributions as wages | Convert distributions to W-2 wages | Additional employment taxes, penalties, and interest |
| Disallowed losses exceeding the basis | Reduce or eliminate loss deductions | Increased taxable income for shareholders |
| Personal expenses reclassified | Remove corporate deductions, add to shareholder income | Corporate income increases, shareholder compensation increases |
| Interest on shareholder loans | Impute interest income to the shareholder | Additional taxable income |
| Shareholder benefit adjustments | Reclassify fringe benefits as taxable wages | Additional W-2 income and employment taxes |
Penalty Exposure in S Corporation Examinations
Beyond additional tax and interest, certain compliance failures can result in penalties.
Common S Corporation Penalties:
| Penalty Type | When Applied | Penalty Amount |
|---|---|---|
| Accuracy-related penalty | Substantial understatement of tax or negligence | 20% of underpayment |
| Employment tax penalties | Failure to properly classify and pay employment taxes | Varies by circumstances |
| Failure to file penalty | Late filing of Form 1120-S | $255 per month per shareholder (2026 amount) |
| Negligence or disregard of rules | Careless or intentional disregard of tax rules | 20% of underpayment |
Penalties can often be abated if you demonstrate reasonable cause for the compliance failure.
Moving Forward After an S Corporation Examination
Whether the examination results in no change, agreed adjustments, or a dispute, implementing improvements prevents future issues.
Post-Examination Actions:
- Implement compliance improvements: Address any identified weaknesses in documentation or procedures
- Update compensation methodology: If reasonable compensation was questioned, document your updated approach
- Improve basis tracking: Implement annual basis calculations if not previously maintained
- Review with a professional advisor: Discuss examination results and compliance improvements with your CPA
Professional Guidance Through S Corporation Examinations
S corporation examinations involve complex tax issues requiring specialized knowledge. Reasonable compensation determinations, basis calculations, and proper classification of shareholder transactions require expertise beyond basic tax preparation.
Matthew L. Ward, CPA at Bluegrass Professional Associates, has over 25 years of experience representing S corporation owners through IRS examinations. With a direct, no-nonsense approach and deep expertise in S corporation compliance, Matthew personally handles complex examination matters while staff members manage administrative functions.
If your S corporation receives an examination notice or if you want to implement proactive compliance practices that reduce examination risk, professional guidance ensures you protect your interests while maintaining focus on running your business.
Contact Bluegrass Professional Associates today to discuss how expert S corporation advisory services can help you navigate examination procedures with confidence.
Sources
- IRS Internal Revenue Manual 4.1.5 – Case Building, Classification, Storage and Delivery – https://www.irs.gov/irm/part4/irm_04-001-005
- IRS Internal Revenue Manual (IRM) 4.1.5.3.6.1 – Potentially Productive Issues on an S Corporation Return and Shareholder Returns – https://www.irs.gov/irm/part4/irm_04-001-005#idm140220973034368
- IRS S Corporation Stock and Debt Basis – https://www.irs.gov/businesses/small-businesses-self-employed/s-corporation-stock-and-debt-basis
- IRS Fact Sheet FS-2008-25 – Wage Compensation for S Corporation Officers – https://www.irs.gov/pub/irs-news/fs-08-25.pdf
- IRS Form 7203 Instructions – S Corporation Shareholder Stock and Debt Basis Limitations – https://www.irs.gov/forms-pubs/about-form-7203
- IRS Form 1120-S Instructions – https://www.irs.gov/forms-pubs/about-form-1120-s
- IRS Publication 1 – Your Rights as a Taxpayer – https://www.irs.gov/publications/p1
- IRS Reasonable Compensation Job Aid for IRS Valuation Professionals