Small business owners are required to maintain accurate records and follow IRS rules.
Most small business tax mistakes are not intentional. They happen when documentation is incomplete, records are unclear, or IRS rules are applied incorrectly.
The IRS provides clear guidance on deductions, worker classification, depreciation, record-keeping, and compensation. Compliance depends on following those rules and maintaining supporting documentation.
About This Series
This series explains 10 common small business tax mistakes, based on IRS publications and requirements.
Each article focuses on one issue and explains the IRS rules that apply.
Common Small Business Tax Mistakes
1. Mixing Personal and Business Finances
IRS Publication 583 requires businesses to keep records that clearly show income and expenses.
When personal and business transactions are combined, documentation becomes difficult to support, and financial reporting becomes unreliable.
→ Read the full article on mixing personal and business finances
2. Not Tracking All Business Expenses
IRS Publication 535 allows deductions for ordinary and necessary business expenses, but only when properly recorded and documented.
Failure to track expenses can result in overstated taxable income and incomplete records.
→ Read the full article on tracking all business expenses
3. Not Keeping Records for All Accounts
Internal Revenue Code §6001 requires taxpayers to maintain records sufficient to establish income and deductions.
This includes all accounts used for business activity.
→ Read the full article on maintaining complete business account records
4. Spending Money Just to Reduce Taxes
IRS Publication 535 explains that deductions reduce taxable income. They do not reimburse the full cost of a purchase.
Spending solely to lower taxable income does not automatically improve financial position.
→ Read the full article on business spending and tax deductions
5. Misclassifying Employees as Independent Contractors
IRS Publication 15-A outlines common law rules used to determine worker classification.
Improper classification can result in employment tax liability, penalties, and interest.
→ Read the full article on IRS worker classification rules
6. Not Using Available Tax-Deferred Accounts
IRS Publication 560 and IRS Publication 969 explain the contribution rules for retirement plans and Health Savings Accounts.
Failure to understand eligibility and contribution limits may result in higher taxable income than necessary.
→ Read the full article on retirement plans and HSA tax rules
7. Not Keeping Proper Documentation
IRS Publication 583 and IRS Publication 463 outline substantiation requirements for certain expenses, including travel and vehicle use.
Deductions must be supported by adequate records.
→ Read the full article on IRS documentation requirements
8. Incorrect Depreciation
IRS Publication 946 provides rules for depreciating business property.
Improper depreciation methods can result in disallowed deductions or required adjustments.
→ Read the full article on depreciation rules for small businesses
9. Improper Allocation of Business and Personal Expenses
IRS Publication 463 and IRS Publication 587 explain the allocation requirements for mixed-use expenses, such as vehicles and home offices.
Only the business portion of a mixed-use expense is deductible.
→ Read the full article on allocating business and personal expenses correctly
10. Paying Yourself Incorrectly
Compensation rules vary by entity type. IRS guidance for S corporations, sole proprietors, and partnerships outlines specific requirements.
An improper compensation structure can result in payroll tax adjustments and penalties.
→ Read the full article on paying yourself correctly based on entity type
Sources
This series is based on guidance published by the Internal Revenue Service, including:
• IRS Publication 535 — Business Expenses
• IRS Publication 583 — Starting a Business and Keeping Records
• IRS Publication 463 — Travel, Gift, and Car Expenses
• IRS Publication 946 — How to Depreciate Property
• IRS Publication 560 — Retirement Plans for Small Business
• IRS Publication 969 — Health Savings Accounts and Other Tax-Favored Health Plans
• IRS Publication 587 — Business Use of Your Home
• IRS Publication 15-A — Employer’s Supplemental Tax Guide
• Internal Revenue Code §6001 — Recordkeeping Requirements
Final Note on Compliance
IRS record keeping requirements and documentation standards are not optional. Accurate reporting depends on maintaining complete records, applying classification rules correctly, and following published IRS guidance.
This content is for informational purposes and is based on IRS publications. Individual tax situations vary. Consult your tax preparer, CPA, or accountant regarding your specific circumstances.