What Can I Deduct If I Have an S-Corp?
A complete, IRS-verified guide to every deduction available to S-Corporation owners — straight from the official Form 1120-S instructions.
An S-Corporation (S-Corp) is a pass-through entity that files its income tax return on Form 1120-S. The corporation itself generally does not pay federal income tax — instead, income, deductions, and credits flow through to the shareholders and are reported on each shareholder’s personal return via Schedule K-1. Knowing exactly which expenses the corporation can deduct directly on Form 1120-S is essential to minimizing your total tax burden legally.
Files Form 1120-S
Every S-Corp must file Form 1120-S annually to report income, deductions, credits, and distribute each shareholder’s share via Schedule K-1.
Pass-Through Taxation
The S-Corp itself typically pays no federal income tax. Profits and losses pass through to shareholders and are taxed at the individual level.
Reasonable Salary Required
Shareholder-employees who perform services must receive a reasonable salary subject to payroll taxes before taking distributions. This is an IRS requirement.
Filing Deadline
Form 1120-S is due on the 15th day of the 3rd month after the end of the tax year (March 15 for calendar-year corporations). A 6-month extension is available.
The following deductions are reported directly on Form 1120-S (Lines 7–20) and reduce the corporation’s ordinary business income before it passes through to shareholders. All deductions must be ordinary, necessary, and directly related to the business.
Line 7 & 8 — Form 1120-S
Officer & Employee Compensation
Salaries and wages paid to officers and employees are fully deductible. Shareholder-employees must receive a reasonable salary — the IRS scrutinizes attempts to pay below-market wages to avoid payroll taxes.
Line 9 — Form 1120-S
Repairs & Maintenance
Deductible amounts for incidental repairs and maintenance that do not add to the property’s value or appreciably prolong its useful life.
Line 10 — Form 1120-S
Bad Debts
Specific business debts that became worthless during the tax year and were previously included in income. Only the specific charge-off method is allowed for tax purposes.
Line 11 — Form 1120-S
Rents
Rent paid or accrued for business property used in the trade or business. Includes office space, equipment, and vehicles rented at arm’s length.
Line 12 — Form 1120-S
Taxes & Licenses
Deductible taxes include state and local income taxes, real estate taxes on business property, payroll taxes (employer portion: Social Security, Medicare, FUTA, SUTA), and business licenses and regulatory fees.
Line 13 — Form 1120-S
Interest Expense
Interest paid or accrued on business debt is deductible, subject to the business interest expense limitation rules under IRC Section 163(j). Small businesses meeting the gross receipts test may be exempt from this limitation.
Line 14 — Form 1120-S
Depreciation (Section 179 & Bonus)
Depreciation on business assets using MACRS. Includes Section 179 expensing of qualifying property and bonus depreciation under IRC Section 168(k). Use Form 4562 to calculate and report.
Line 17 — Form 1120-S
Pension & Profit-Sharing Plans
Contributions to qualified retirement plans for employees — including SEP-IRAs, SIMPLE IRAs, and 401(k) plans — are deductible. Contributions must be made by the tax return due date (including extensions).
Line 18 — Form 1120-S
Employee Benefit Programs
Costs of employee benefit programs such as health insurance, group-term life insurance (up to $50,000), dependent care assistance programs, and other fringe benefits provided to employees (excluding shareholder-employees who own more than 2%).
Line 19 — Form 1120-S
Energy-Efficient Commercial Buildings
A deduction under IRC Section 179D for qualifying energy-efficient commercial building improvements installed on property owned by the S-Corp. Available for qualifying HVAC, lighting, and building envelope improvements.
Line 20 — Form 1120-S
Other Deductions
A broad category including: advertising, utilities, professional fees (legal, accounting), office supplies, business insurance, telephone and internet, business-related subscriptions, and other ordinary business expenses not listed on a specific line.
These Rules Have Specific Limits — Know Them
The IRS imposes specific limitations on travel, meals, and entertainment deductions. Getting these wrong is a common audit trigger for S-Corps.
Business Travel
Ordinary and necessary travel expenses away from the principal place of business are 100% deductible. Includes transportation, lodging, and incidental expenses. Must be business-related and away from the tax home overnight.
Business Meals
Business meals are 50% deductible if the taxpayer (or an employee) is present, the meal is not lavish or extravagant, and there is a bona fide business purpose. Meals while traveling for business also follow the 50% limit.
Entertainment
Client entertainment expenses (tickets to events, golf outings, etc.) are generally not deductible under current tax law (Tax Cuts and Jobs Act, in effect since 2018). This rule applies even if business is discussed.
Qualified Transportation Fringes
Employer-provided transportation benefits (parking, transit passes) are generally not deductible for the employer when provided to employees, unless treated as taxable compensation to the employee.
📄 How Pass-Through Deductions Work
Not all S-Corp deductions are taken at the corporate level on Form 1120-S. Certain items are separately stated on Schedule K and passed through to each shareholder via Schedule K-1, where they are deducted on the shareholder’s individual return (Form 1040).
These pass-through items include: charitable contributions, Section 179 deductions (to the extent not taken at the corporate level), investment interest expense, rental real estate income or loss, and various tax credits.
Shareholders can only deduct their share of S-Corp losses up to their basis in the corporation (stock basis plus debt basis). Losses in excess of basis are suspended and carried forward.
| Expense | Status | Why |
|---|---|---|
| Federal income taxes paid by the corporation | NOT DEDUCTIBLE | Federal income taxes are not a deductible business expense under the IRC. |
| Entertainment (client events, concerts, golf) | NOT DEDUCTIBLE | Eliminated by the Tax Cuts and Jobs Act of 2017, effective 2018 forward. |
| Club membership dues | NOT DEDUCTIBLE | Dues for country clubs, golf clubs, airline clubs, and social clubs are not deductible per IRS rules. |
| Fines and penalties paid to a government | NOT DEDUCTIBLE | Amounts paid as fines or penalties for violations of law cannot be deducted. |
| Lobbying expenses | NOT DEDUCTIBLE | Amounts paid to influence legislation at the federal, state, or local level are not deductible. |
| Business meals — full amount | 50% LIMIT | Only 50% of qualifying business meals are deductible. The other 50% is not. |
| Business start-up costs — full amount in year 1 | LIMITED | Up to $5,000 can be deducted in the first year; the remainder must be amortized over 180 months per IRC §195. |
| Excess business interest expense | LIMITED | Business interest expense may be limited under IRC §163(j) if the business exceeds the gross receipts threshold. |
📅 Form 1120-S: Key Filing Facts
- 🔴
Increased penalty for failure to file: The per-shareholder, per-month penalty for late filing of Form 1120-S has been updated for 2025. File on time or request an extension.
- 🔴
Domestic Research & Experimental Expenditures: Under current law, domestic R&E costs must be capitalized and amortized over 5 years (15 years for foreign research) rather than expensed immediately. This rule, from the Tax Cuts and Jobs Act, continues to apply.
- 🔴
Qualified Sound Recording Productions: Updated rules apply to certain qualified sound recording production costs treated as a separate deduction category.
- 🔴
Farmland Gain Exclusion: A new provision addresses gain from the sale or exchange of qualified farmland property to qualified farmers — reportable on Schedule K-1 with an updated code.
- 🔴
Electronic Payments: The IRS continues to require electronic deposits via EFTPS for most corporate tax payments. Direct deposit of any refund is available.
The Reasonable Salary Requirement — Do Not Ignore It
S-Corp shareholder-employees who provide services to the corporation must pay themselves a reasonable salary through payroll (W-2) before taking distributions. The IRS actively audits S-Corps where shareholders take little or no salary but large distributions to avoid Social Security and Medicare taxes. Failure to comply can result in reclassification of distributions as wages, back payroll taxes, interest, and penalties.
- ✅ Payroll processed and reasonable salary paid to shareholder-employees
- ✅ All officer compensation reported separately on Line 7 of Form 1120-S
- ✅ Retirement plan contributions made before the due date (including extensions)
- ✅ Health insurance for >2% shareholders added to W-2 Box 1 and reported correctly
- ✅ Meals documented with business purpose, attendees, and receipts (50% limit applied)
- ✅ Entertainment expenses removed — not deductible since 2018
- ✅ Depreciation calculated on Form 4562 (Section 179 and bonus depreciation)
- ✅ Business interest expense reviewed for IRC §163(j) limitation
- ✅ Start-up costs properly amortized if applicable
- ✅ Schedule K-1 prepared and distributed to all shareholders
- ✅ Return filed or extension requested by March 15
💼 Maximize Your S-Corp Deductions Legally
Running an S-Corp comes with significant tax advantages — but only if you apply the deductions correctly. A qualified accountant can help you capture every dollar you are entitled to without triggering an IRS audit.
