Startup Tax Deductions Every New Business Owner Should Know in 2026

The biggest startup tax deductions are the $5,000 startup-cost and $5,000 organizational-cost write-offs in year one, immediate expensing of domestic R&D, and 100% bonus depreciation on equipment. After those, a new business deducts its ordinary operating costs (salaries, contractors, software, rent, insurance) in the year it pays or incurs them.

The rest of this guide explains each line, starting with the distinction that trips up most first-year returns: costs before you open versus costs after.

Whether a cost is a startup cost or an ordinary deduction depends on timing. Costs you incur before the business begins operating are startup costs under §195. The same kind of cost incurred after you begin is an ordinary and necessary business expense under §162, fully deductible that year.

A business generally begins when it starts the activities it was formed for, which is not necessarily the day of first revenue. A SaaS company that has hired engineers and is building product has usually begun. A founder still researching markets and talking to lawyers before committing to a business has not.

This matters because the startup-cost allowance is small. If you incur $60,000 of pre-opening costs, the $5,000 allowance is gone, and the full $60,000 amortizes at $333 a month for 15 years. The same $60,000 spent after you begin is deductible in full that year. Research and experimental costs follow the R&E rules (now §174A) rather than §195, and interest, taxes and R&E are excluded from startup costs by statute.

In the year your business begins, you can elect to deduct up to $5,000 of startup costs and, separately, up to $5,000 of organizational costs. Each $5,000 allowance is reduced dollar for dollar by the amount that category exceeds $50,000, so it disappears at $55,000. Anything not deducted is amortized ratably over 180 months starting in the month the business begins. Under current regulations the election is deemed made unless you elect out on a timely filed return.

Startup costs (§195) are costs of investigating or creating a business before it opens:

• Market research and customer discovery before launch
• Travel to evaluate locations, suppliers or partners
• Pre-launch advertising
• Wages and consultant fees for training and setup before opening

Organizational costs (§248 for corporations, §709 for partnerships) are costs of creating the entity:

• Delaware and state filing fees
• Legal fees for the charter, bylaws and initial board consents
• Accounting fees for setting up the entity

Costs of issuing or selling stock, such as fundraising legal fees and placement fees, are neither. They reduce paid-in capital and are not deductible or amortizable. For example, a new C-Corp with $3,500 of formation costs and $12,000 of pre-launch costs deducts all $3,500 of organizational costs plus $5,000 of startup costs, and amortizes the remaining $7,000 at about $38.89 a month.

For tax years beginning after December 31, 2024, domestic research and experimental expenditures are deductible in the year paid or incurred under new §174A, added by the One Big Beautiful Bill Act (P.L. 119-21). You can instead elect to capitalize and amortize them over at least 60 months, which can make sense if you want to preserve NOLs for later. Foreign research stays under §174 and is amortized over 15 years.

For software startups this is the most valuable change in years. Developer salaries, contractor fees for product work, and cloud costs tied to development were all being capitalized over five years from 2022 to 2024. Unamortized domestic amounts from those years can be deducted in full in 2025 or spread over 2025 and 2026.

Small businesses with average gross receipts of $31 million or less could also elect to apply §174A retroactively to 2022 through 2024 by amended return. Rev. Proc. 2025-28 set the deadline for that election at July 6, 2026, so it has closed for anyone who did not act. Companies that missed it still get the 2025 or 2025 to 2026 catch-up deduction.

Laptops, monitors, servers, furniture and other equipment can usually be deducted in full in the year placed in service. OBBBA made 100% bonus depreciation permanent for qualified property acquired after January 19, 2025, reversing the phase-down that would have left 20% for 2026. The IRS issued interim guidance in Notice 2026-11.

Section 179 is the alternative. For tax years beginning in 2026, Rev. Proc. 2025-32 sets the §179 limit at $2,560,000, reduced dollar for dollar once qualifying purchases exceed $4,090,000. Unlike bonus depreciation, §179 cannot create a loss: it is limited to taxable business income. For a loss-making startup, bonus depreciation is usually the simpler choice, and you can elect out of it by asset class if you would rather depreciate.

Software subscriptions are not equipment. SaaS tools such as your CRM, cloud hosting and design software are ordinary operating expenses, deducted as incurred.

The research credit under §41 is a credit, not a deduction, so it reduces tax dollar for dollar. Most startups can't use an income tax credit while losing money, which is why the payroll tax election matters.

A qualified small business can elect on Form 6765 to apply up to $500,000 of credit a year against payroll taxes: the first $250,000 against the employer share of Social Security and the rest against the employer share of Medicare. To qualify, gross receipts must be under $5 million for the year and the company can't have had gross receipts in any year before the five-year period ending with the current year. The credit is claimed quarterly on Form 8974 with Form 941, starting the quarter after the income tax return is filed.

With §174A expensing back, remember §280C(c): your R&E deduction is reduced by the credit unless you elect a reduced credit on a timely filed original return.

A founder can deduct a home office used regularly and exclusively for the business. The simplified method allows $5 per square foot up to 300 square feet, so $1,500 at most; the regular method uses the actual share of rent, utilities, insurance and repairs. For example, an office that is 15% of a home costing $36,000 a year supports $5,400 of expenses under the regular method.

If your company is a C-Corp, the corporation can't take your home office on its return directly, and since 2018 employees can't deduct unreimbursed expenses. The practical route is an accountable plan: the company reimburses a documented share of home costs, deducts the reimbursement, and you receive it tax-free.

Vehicle use works the same way. The 2026 IRS business mileage rate was 72.5 cents per mile from January 1 to June 30 and 76 cents from July 1 to December 31. Reimburse at the standard rate against a contemporaneous log (date, destination, purpose, miles), or deduct actual costs prorated by business use.

Ordinary operating costs are where most of a startup's deductions end up once it is running:

• Salaries, payroll taxes and benefits, including health insurance the company pays for employees
• Contractor payments, which now need a Form 1099-NEC only once a payee reaches $2,000 (for payments made after December 31, 2025, up from $600)
• Rent, software, cloud hosting, insurance and professional fees
• Business travel: airfare, lodging and 50% of meals while away
• Business meals with clients or colleagues, 50% deductible when you or an employee is present

Entertainment such as event tickets is not deductible. Starting in 2026, §274(o) generally disallows the deduction for food and drink provided on the employer's premises for the employer's convenience, so office snacks and catered team lunches need a fresh look.

We usually tell first-year founders to keep receipts, use a business card for every business expense, and close the books monthly. Most lost deductions come from missing records, not from rules. The figures above were checked against IRS guidance in October 2026, and this is general information, not tax advice for your specific facts.