Tax Deduction

A tax deduction is a business expense that reduces your taxable income. The more legitimate deductions you claim, the less tax you pay. Common deductions include rent, supplies, mileage, insurance, and professional services.

Tax Deduction Definition

A tax deduction is an expense the IRS allows you to subtract from your gross income before calculating taxes owed. Deductions reduce your taxable income — not your tax bill directly (that's a tax credit).

How Deductions Save Money

If you're in the 24% tax bracket and claim a $1,000 deduction, you save $1,000 × 24% = $240 in taxes. The deduction doesn't save you the full $1,000 — it saves you the tax you would have paid on that $1,000.

Common Business Tax Deductions

Office rent — full deduction for business-only space

Home office — simplified method ($5/sq ft, max 300 sq ft) or actual expenses

Business insurance — liability, property, workers' comp, professional liability

Vehicle/mileage — standard rate ($0.70/mile for 2026) or actual expenses

Professional services — CPA, attorney, consultant fees

Marketing and advertising — website, ads, promotional materials

Software subscriptions — QBO, project management, CRM, etc.

Employee salaries and benefits — including health insurance, retirement contributions

Supplies and materials — office supplies, tools, inventory

Travel and meals — business travel (100%) and business meals (50%)

Deductions vs. Credits

Deduction — reduces taxable income (saves you a percentage of the deduction amount)

Credit — reduces tax owed dollar-for-dollar (more valuable per dollar)

How to Track Deductions in QuickBooks

Proper categorization is everything. Every expense in QuickBooks should be assigned to the correct account — these map directly to your tax return line items. Your P&L organized by expense category IS your deduction summary.

FAQ

Q: Can I deduct an expense if I don't have a receipt?

A: The IRS requires documentation. For expenses under $75 (except lodging), you can use bank/credit card statements. Above $75, keep the actual receipt. No documentation = no deduction if audited.

Related Terms

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Related Terms

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Credit

In bookkeeping, a credit is an entry on the right side of a journal entry or T-account that increases certain types of accounts and decreases others. Credits increase liabilities, equity, and revenue accounts. They decrease asset and expense accounts. Every transaction requires at least one credit a

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