Reviewed and updated October 16, 2026
Start with the business purpose
A business expense generally must be ordinary and necessary for your trade or business. Common categories include supplies, advertising, professional fees, business insurance and qualifying rent. Personal spending does not become deductible because it was paid with a business card. Record the purpose while it is still easy to remember.
A deduction reduces taxable income; it does not reimburse the full purchase price. Spend because the business needs an item, then evaluate its tax treatment.
Separate routine costs from special categories
Inventory, equipment, startup expenditures, vehicle use, meals and home-office costs each require closer attention. Buying inventory does not always produce an immediate deduction for everything purchased. Equipment may require depreciation or an applicable expensing election.
For mixed personal and business costs, document a reasonable allocation. A vehicle log should identify business travel, and ordinary commuting is generally personal. Keep invoices and explanations for meals instead of assuming every restaurant charge qualifies.
Build a file your preparer can use
Organize receipts by category and match them to reconciled bank and credit-card accounts. Keep acquisition documents for assets and schedules of business loans. Record reimbursements and refunds so the same expense is not deducted twice.
Before filing, provide your year-end financial statements, payroll reports, contractor details and a list of major purchases. Ask about industry-specific limits and the rules for the tax year being filed. A review before a large purchase gives you more useful choices than sorting out unsupported deductions after year-end.
Official sources
This guide provides general information. The rules depend on the tax year, jurisdiction and your circumstances. Ask our team which filing or planning steps apply to you.
