Business Tax Deductions Checklist: Every Deduction Small Business Owners Should Know
Last updated: 2026-03-27
Summary:Business tax deductions reduce your taxable income, saving you money on both income tax and self-employment tax. The key rule: an expense must be "ordinary and necessary" for your trade or business to be deductible (IRC Section 162). This guide covers every major deduction category — home office, vehicle (72.5¢/mile in 2026), equipment (Section 179: up to $2,560,000; bonus depreciation: 100% under OBBBA), insurance, retirement (Solo 401k: $72,000 max), health insurance, meals, travel, professional services, marketing, software, education, phone/internet, and the QBI deduction (Section 199A: up to 20% of qualified business income, now permanent) — plus documentation requirements and common audit triggers. A sole proprietor in the 24% tax bracket who finds $10,000 in missed deductions saves approximately $3,930 ($2,400 income tax + $1,530 SE tax).
How do you deduct a home office?
To claim the home office deduction, you must use a portion of your home regularly and exclusivelyfor business. The space does not need to be a separate room — a dedicated desk area in a corner qualifies — but it cannot double as personal space (no gaming setup at your business desk). You have two methods:
Simplified Method
- •$5 per square foot of dedicated home office space, up to 300 sq ft
- •Maximum deduction: $1,500 per year
- •No depreciation calculation, no tracking individual expenses
- •Best for: small offices, renters, people who want simplicity
Actual Expense Method
- •Calculate the percentage of your home used for business (e.g., 200 sq ft office / 2,000 sq ft home = 10%)
- •Deduct that percentage of: mortgage interest or rent, property taxes, utilities, homeowner's insurance, repairs, and depreciation
- •Direct expenses (painting only the office) are 100% deductible
- •No cap on the deduction (limited to net business income)
- •Best for: larger offices, homeowners with significant mortgage/tax costs
Example (Actual Method):Your home is 2,000 sq ft and your office is 200 sq ft (10%). Annual costs: $18,000 rent + $2,400 utilities + $1,200 insurance = $21,600. Home office deduction: $21,600 × 10% = $2,160. The simplified method would yield only $1,000 (200 sq ft × $5), so the actual method saves $1,160 more.
How do you deduct vehicle expenses?
If you use your personal vehicle for business, you can deduct the business portion using one of two methods. You must choose one method per vehicle and generally stick with it (you can switch in future years for the same vehicle, with some limitations).
Standard Mileage Rate (2026)
- •72.5 cents per mile for business miles driven (IRS standard mileage rate for 2026)
- •Plus tolls and parking fees (deductible separately)
- •Requires a mileage log with date, destination, business purpose, and miles driven
- •Must use this method in the first year if you want to use it at all for that vehicle
Actual Expense Method
- •Track all vehicle costs: gas, oil, tires, repairs, insurance, registration, depreciation, lease payments
- •Multiply total costs by your business-use percentage (e.g., 12,000 business miles / 20,000 total = 60%)
- •Generally better for expensive vehicles or high-cost areas
Example:You drive 15,000 business miles in 2026. Standard mileage: 15,000 × $0.725 = $10,875. Actual expenses: $8,000 total vehicle costs × 75% business use = $6,000. In this case, the standard mileage rate gives a larger deduction.
Important: Commuting from home to your regular place of business is NOT deductible. However, if your home office qualifies as your principal place of business, drives from your home office to client sites are business miles.
How do you deduct equipment and supplies (Section 179)?
Business equipment normally must be depreciated (deducted gradually) over its useful life — 5 years for computers, 7 years for office furniture, etc. However, Section 179 and bonus depreciation let you deduct the full cost in the year of purchase.
Section 179 Deduction (2026)
- •Deduct up to $2,560,000 of qualifying equipment and software in the year purchased (increased under the One Big Beautiful Bill Act)
- •Phase-out begins at $4,090,000 in total equipment purchases
- •Qualifying assets: computers, office furniture, machinery, vehicles (with limits), software, certain improvements to nonresidential property
- •Cannot create or increase a net loss — deduction limited to your business income
Bonus Depreciation (2026)
- •100% bonus depreciation for qualifying property placed in service after January 19, 2025 — restored by the One Big Beautiful Bill Act (OBBBA)
- •Can be used on new and used property (as long as it is new to the taxpayer)
- •No dollar limit (unlike Section 179); can create or increase a net loss
- •The OBBBA reversed the TCJA phase-down that had reduced bonus depreciation from 80% (2023) to 60% (2024) to 40% (2025); it is now permanently 100%
- •Taxpayers may elect 40% (or 60% for long-production-period property) instead of 100% for property placed in service during the first tax year ending after Jan. 19, 2025
Everyday supplies— office supplies, printer ink, paper, packaging materials, cleaning supplies, and small tools under $2,500 — are deductible as current expenses under the de minimis safe harbor election. No depreciation needed.
Which insurance premiums are deductible?
Business insurance premiums are fully deductible as ordinary business expenses. Deductible premiums include:
- •General liability insurance
- •Professional liability / errors & omissions (E&O)
- •Workers' compensation insurance
- •Commercial property insurance
- •Commercial auto insurance
- •Business owner's policy (BOP)
- •Cyber liability insurance
- •Business interruption insurance
- •Key person life insurance (only premiums, not if you are the beneficiary)
Personal insurance (homeowner's, personal auto, personal umbrella) is NOT deductible as a business expense. However, the business-use percentage of your homeowner's insurance can be deducted through the home office deduction.
How much can you deduct in retirement contributions?
| Plan Type | 2026 Limit | Catch-Up (50+) | Key Notes |
|---|---|---|---|
| SEP IRA | 25% of net SE earnings (max $72,000) | None | Employer contributions only; easiest to set up |
| Solo 401(k) | $24,500 employee + 25% employer (max $72,000 total) | +$8,000 (ages 50-59, 64+); +$11,250 (ages 60-63) | Higher limits for lower earners; Roth option available |
| SIMPLE IRA | $16,500 employee + 3% employer match | +$3,500 | For businesses with 100 or fewer employees |
| Traditional IRA | $7,500 | +$1,100 | Deductibility may be limited if you have a workplace plan |
Retirement contributions reduce your taxable income (income tax) but do not reduce self-employment tax. The contribution itself grows tax-deferred (or tax-free with Roth). For a sole proprietor earning $100,000 in net profit, a SEP IRA contribution of up to $18,587 (25% of net SE earnings after the SE tax deduction) is fully deductible.
Solo 401(k) advantage: If your net SE earnings are under $100,000, a Solo 401(k) usually allows a larger contribution than a SEP IRA because of the $24,500 employee deferral component. A freelancer earning $60,000 can contribute $24,500 (employee) + $11,145 (25% employer) = $35,645 to a Solo 401(k), versus only $11,145 to a SEP IRA.
Can self-employed individuals deduct health insurance premiums?
Yes. Self-employed individuals can deduct 100% of health insurance premiums for themselves, their spouse, and their dependents as an "above-the-line" deduction on Form 1040. This includes medical, dental, vision, and qualifying long-term care insurance.
- •Reduces income tax but does NOT reduce self-employment tax
- •Cannot exceed your net self-employment income
- •Not available for months when you were eligible for an employer-sponsored plan (including a spouse's plan)
- •For S-Corp owners: the company must pay or reimburse premiums, and the amount is included in your W-2 wages
Example: You pay $600/month for a family health plan ($7,200/year) and $100/month for dental ($1,200/year). Total deduction: $8,400. In the 24% bracket, this saves you $2,016 in income tax.
What are the rules for deducting travel and meals?
Business Travel
Travel expenses are 100% deductible when the primary purpose of the trip is business. Deductible travel costs include:
- •Airfare, train, bus, and other transportation to and from the business destination
- •Hotel or lodging at the business destination
- •Rental cars, taxis, rideshare (Uber/Lyft) at the destination
- •Baggage fees, tips, and dry cleaning while traveling
- •Wi-Fi fees, business center costs, and conference registration
If a trip is mixed business and personal, only the business days and directly business-related expenses are deductible. Airfare may still be fully deductible if the primary purpose was business.
Business Meals
- •50% deductible for meals with clients, prospects, or business associates where business is discussed
- •50% deductible for meals while traveling for business
- •Must not be "lavish or extravagant" (reasonable under the circumstances)
- •Document: date, amount, location, attendees, and business purpose
- •Entertainment expenses are NOT deductible(sporting events, concerts, golf outings) — this changed under TCJA in 2018
Can you deduct professional services?
Fees paid to professionals for business-related services are fully deductible:
- •Accounting and bookkeeping— CPA fees, tax preparation for your business return, bookkeeping services, payroll processing
- •Legal fees— business formation, contract review, trademark registration, collections (NOT personal legal matters)
- •Consulting— business coaches, marketing consultants, IT consultants
- •Freelancers and contractors— web developers, designers, virtual assistants, writers
Note: The fee for preparing the personal portion of your tax return (Form 1040, Schedules A and B) is NOT a business deduction. Only the business-related portion (Schedule C, Schedule SE) is deductible.
Are marketing and advertising expenses deductible?
Yes. Marketing and advertising costs are 100% deductible as long as they relate to your business. This includes:
- •Website hosting, domain registration, and website design/development
- •Social media advertising (Facebook, Instagram, LinkedIn, TikTok ads)
- •Google Ads, Bing Ads, and other search engine marketing
- •Business cards, brochures, flyers, and print materials
- •Email marketing platforms (Mailchimp, ConvertKit, Constant Contact)
- •SEO services, content marketing, and copywriting
- •Trade show booth fees, sponsorships, and promotional items
- •Signage for your business location
Can you deduct software and subscriptions?
Software subscriptions and digital tools used for business are fully deductible. Common deductible subscriptions include:
- •Accounting software (QuickBooks, Xero, FreshBooks, Wave)
- •Project management tools (Asana, Monday, Trello, Notion)
- •Communication tools (Zoom, Slack, Microsoft Teams, Google Workspace)
- •Design tools (Adobe Creative Cloud, Canva, Figma)
- •CRM software (HubSpot, Salesforce, Zoho)
- •Cloud storage (Dropbox, Google Drive, iCloud for business)
- •Industry-specific software (CAD, legal research, medical billing)
- •E-commerce platforms (Shopify, WooCommerce, BigCommerce)
SaaS subscriptions are deducted as current expenses (not depreciated). Perpetual software licenses over $2,500 may need to be depreciated over 3 years unless you elect Section 179 or de minimis safe harbor.
Are education and training expenses deductible?
Education that maintains or improves skills in your current business is deductible. Education that qualifies you for a new career is NOT deductible. Examples:
- ✓Online courses related to your current business (marketing, management, technical skills)
- ✓Industry conferences, workshops, and seminars
- ✓Professional certifications required to maintain your license
- ✓Books, publications, and trade journals related to your field
- ✓Coaching and mentoring programs for your current business
- ✗Law school if you are a plumber (qualifies you for a new career)
- ✗College degree not related to your current business
Can you deduct your phone and internet bill?
You can deduct the business-use percentage of your phone and internet bills. If you use your phone 70% for business, you deduct 70% of the bill. If you have a separate business phone line, it is 100% deductible.
- •Cell phone service (business-use percentage)
- •Home internet service (business-use percentage, or included in home office deduction)
- •Dedicated business phone line (100%)
- •VoIP services (Google Voice, RingCentral, Grasshopper) — 100% if business-only
- •Mobile hotspot, data plan upgrades for business use
Determine your business-use percentage by tracking usage for a representative month. Keep a log of business vs. personal calls and data usage. Once established, you can apply the same percentage throughout the year unless your usage patterns change significantly.
How should you document business deductions?
The IRS follows the Cohan rule — you must substantiate deductions with adequate records. Here are best practices:
What are common audit triggers for business deductions?
The IRS uses algorithms (the DIF score) to flag returns that are statistically unusual. Here are the most common triggers:
- •Business losses for 3+ consecutive years— triggers the "hobby loss" presumption under IRC Section 183
- •100% business use of a vehicle— the IRS knows almost no one uses a car exclusively for business
- •Large meals and entertainment deductions— disproportionate to revenue
- •Home office deduction with a W-2 job— requires your home office to be your principal place of business
- •Deductions that are disproportionately large relative to your income or industry norms
- •Round numbers everywhere— suggests estimation rather than actual records
- •High cash revenue businesses— restaurants, bars, retail, salons face higher audit rates
- •Large charitable deductions relative to income
Bottom line: Claim every deduction you are entitled to, but make sure you can back it up with documentation. The goal is not to minimize deductions out of fear — it is to maximize legitimate deductions and have the records to support them.
What is the Qualified Business Income (QBI) deduction?
The QBI deduction (Section 199A) allows eligible self-employed individuals and small business owners to deduct up to 20% of qualified business incomefrom pass-through entities — sole proprietorships, partnerships, S-Corps, and certain trusts. This is an "above-the-line" deduction that reduces your income tax (but not your self-employment tax). The One Big Beautiful Bill Act (OBBBA) made this deduction permanent — it no longer has an expiration date.
2026 Income Thresholds
- •Full deduction: Available if taxable income is below ~$200,000 (single) or ~$400,000 (married filing jointly)
- •Phase-out range:$200,000–$275,000 (single) or $400,000–$550,000 (MFJ)
- •Above phase-out: Deduction may be limited by W-2 wages paid and/or the unadjusted basis of qualified property held by the business
- •Specified service trades or businesses (SSTBs) — including law, medicine, accounting, consulting, athletics, and financial services — are fully phased out above the threshold
How to Calculate the QBI Deduction
- 1.Calculate your QBI: net business income minus business-related deductions (same as Schedule C net profit for sole proprietors)
- 2.Take the lesser of 20% of QBI or 20% of your taxable income (before the QBI deduction)
- 3.If above the phase-out threshold, apply the W-2 wages/qualified property limitation
Example:A sole proprietor earns $100,000 in net business profit and has total taxable income of $85,000 (after the standard deduction and half of SE tax). The QBI deduction is the lesser of 20% × $100,000 = $20,000 or 20% × $85,000 = $17,000. The deduction is $17,000, which at a 22% marginal tax bracket saves $3,740 in federal income tax. This is one of the most valuable deductions available to pass-through business owners.
Minimum deduction (new for 2026): If your QBI is at least $1,000 and you materially participate in the business, you are guaranteed a minimum $400 deduction even if the standard calculation produces less.
Official Resources
- IRS: Qualified Business Income Deduction (Section 199A)
- IRS: Deducting Business Expenses (Publication 535)
- IRS: Home Office Deduction
- IRS: Topic No. 510 — Business Use of Car
- IRS: Section 179 Deduction
- IRS: Publication 463 — Travel, Gift, and Car Expenses (PDF)
- IRS: 2026 Standard Mileage Rate (72.5 cents per mile)
- IRS: One Big Beautiful Bill Act Provisions (100% Bonus Depreciation & Permanent QBI)
Frequently Asked Questions
Can I deduct expenses if I don't have receipts?
The IRS requires documentation for all business deductions. Without receipts, you risk having deductions disallowed in an audit. However, you can reconstruct records using bank statements, credit card statements, calendars, and logs. For expenses under $75 (except lodging), the IRS does not require a receipt, but you still need a record of the amount, date, place, and business purpose. Best practice: use a receipt-scanning app (Dext, Expensify, or your phone camera) and photograph receipts immediately.
What is the difference between a tax deduction and a tax credit?
A tax deduction reduces your taxable income, while a tax credit directly reduces your tax bill dollar-for-dollar. For example, a $1,000 deduction in the 24% bracket saves you $240 in tax, but a $1,000 tax credit saves you the full $1,000. Credits are more valuable. Common small business credits include the Small Business Health Care Tax Credit, Work Opportunity Tax Credit (WOTC), and R&D Tax Credit.
Can I deduct business expenses paid with personal funds?
Yes, as long as the expense is ordinary and necessary for your business. The source of funds does not matter for deductibility. However, mixing personal and business finances makes bookkeeping harder and raises red flags in audits. Best practice: use a dedicated business bank account and credit card for all business expenses.
How long should I keep records of business deductions?
The IRS generally has three years from the filing date to audit your return. However, if they suspect you underreported income by 25% or more, they have six years. If you file a fraudulent return or fail to file, there is no time limit. Best practice: keep all business tax records for at least seven years. Keep records related to property, equipment, and depreciation for as long as you own the asset plus seven years after disposal.
Can I deduct the cost of clothing for work?
Only if the clothing is required for your work AND is not suitable for everyday wear. Uniforms, safety gear (hard hats, steel-toe boots), and profession-specific attire (medical scrubs, theatrical costumes) are deductible. General business attire — even if you only wear it for work — such as suits, dresses, or business casual clothing, is NOT deductible because it is considered suitable for everyday wear.
What triggers an IRS audit on business deductions?
Common audit triggers include: claiming a home office deduction (especially if you also have a W-2 job), reporting a business loss for multiple consecutive years (hobby loss rule), deducting 100% of vehicle use as business, having significantly higher deductions than others in your income bracket, large cash transactions, round numbers on every line item (suggests estimation rather than actual records), and inconsistencies between reported income and lifestyle (deposits exceeding reported income).
Can I deduct startup costs before my business earns revenue?
Yes. You can deduct up to $5,000 in startup costs in the year your business begins operating, with the remainder amortized over 180 months (15 years). The $5,000 deduction phases out dollar-for-dollar if total startup costs exceed $50,000. Qualifying startup costs include market research, advertising to open the business, employee training before opening, travel to set up the business, and professional fees (legal, accounting) for setting up the business entity.
Is the home office deduction worth the audit risk?
Yes, if you legitimately qualify. The IRS has stated that claiming a home office does not automatically trigger an audit. The key requirement is that you use the space regularly and exclusively for business — no dual-purpose rooms. The simplified method ($5 per square foot, up to 300 sq ft = $1,500 max) is easy to claim and defensible. The actual expense method yields larger deductions but requires more documentation. If you genuinely use a dedicated space for your business, do not leave money on the table out of audit fear.
Can I deduct my cell phone bill?
You can deduct the business-use percentage of your cell phone bill. If you use your phone 60% for business and 40% for personal use, you can deduct 60% of the monthly bill. If you have a separate phone exclusively for business, 100% is deductible. The IRS expects you to have a reasonable method for determining your business-use percentage — a log for a representative month is generally sufficient.
Video Guides
Free Tools & Calculators
Compare the simplified method ($5/sq ft, max $1,500) vs the regular method for your home office deduction. See which saves you more on taxes.
Free business expense tracker with IRS categories. Log expenses by date, category, and payment method. Auto-calculates totals. Export as CSV or PDF. No signup required.
Free IRS-compliant mileage log. Track trips with date, destination, purpose, and odometer readings. Auto-calculates deductions at 2026 IRS rate ($0.70/mile). Export CSV or PDF.
Calculate Section 179, bonus depreciation, and first-year equipment deductions. See tax savings and effective cost for business equipment purchases. Free, no signup.
Related Resources on This Site
Helpful guides
- Professional Liabilityprofessional liability / E&O insurance
- Business Owners Policybusiness owners policy (BOP)
- Business Licensebusiness license requirements by state
- DBA RegistrationDBA / fictitious name registration
This is general information, not tax or legal advice. Tax deduction rules, limits, and rates change annually. Always consult a qualified tax professional (CPA or Enrolled Agent) for advice specific to your situation. Sources: IRS.gov Publications 535, 587, 463, and 946; SBA.gov.