Year-End Tax Planning for Small Business Owners: 15 Strategies to Reduce Your Tax Bill

By Yarik Yarosh, CPA ·September 5, 2026 ·3 min read

Written by Yarik Yarosh, CPA (US & Canada) September 5, 2026 · FL CPA license AC61704 · CPA Ontario

Year-end tax planning is the most valuable planning window for small business owners. The decisions made between October and December determine the current year’s tax bill. Most strategies fall into two categories: accelerating deductions into the current year and deferring income to the next year. The net effect shifts taxable income from a higher-tax year to a lower-tax year (or delays the tax payment, providing a time-value-of-money benefit).

✓Key takeaway

15 year-end tax strategies ranked by potential impact:

High impact ($5,000+ savings):

Maximize retirement plan contributions: Solo 401(k) allows up to $70,000 (2025). Deadline: December 31 for employee deferrals, tax filing deadline for employer contributions.
Section 179 / bonus depreciation on equipment: Purchase and place in service before December 31. Full cost deductible in Year 1.
S-Corp election for next year: File Form 2553 by March 15 of the election year. Saves 15.3% SE tax on pass-through profits above reasonable salary.
Cost segregation study (real estate owners): Reclassify building components to shorter depreciation lives, creating large Year 1 deductions.
Qualified Improvement Property (QIP): Deduct 100% of interior commercial building improvements placed in service this year.

Medium impact ($1,000-$5,000 savings): 6. Prepaid expenses (12-month rule): Prepay insurance, rent, software subscriptions before December 31. 7. Defer income: Cash-basis businesses can delay invoicing until January. Don’t bill December work until January 1. 8. HSA contribution: $4,300 (self-only) or $8,550 (family) for 2025. Triple tax benefit. 9. Charitable contributions: For C-Corps (deductible at entity level). For pass-throughs, charitable contributions are personal deductions (Schedule A). 10. Bad debt write-off: Write off uncollectible accounts receivable (accrual method) or worthless inventory.

Lower impact but easy ($200-$1,000 savings): 11. Office supplies and equipment: Stock up on supplies, purchase small equipment under the $2,500 de minimis safe harbor. 12. Professional development: Pay for courses, conferences, and certifications before December 31. 13. Accelerate repairs: Schedule vehicle maintenance, equipment repairs, and office maintenance before year-end. 14. Review payroll: S-Corp owners should verify their W-2 salary is reasonable and adjust the final paycheck if needed. 15. Estimated tax review: Calculate the final quarterly payment (due January 15) to avoid underpayment penalties while not overpaying.

How do these stack together?

Hypothetical example

Round numbers. A consulting business (S-Corp) projects $250,000 in net profit before year-end planning. The owner has paid themselves an $80,000 salary throughout the year.

Year-end actions:

Solo 401(k) employer contribution: 25% of $80,000 = $20,000
Solo 401(k) employee deferral (already contributed): $23,500
Purchase new laptop and office furniture: $4,000 (Section 179)
Prepay annual software subscriptions: $3,600
Prepay Q1 coworking space: $2,400
HSA contribution (family): $8,550

Total additional deductions: $38,550

Tax savings:

Federal income tax (32%): $38,550 x 32% = $12,336
No SE tax savings (S-Corp distributions already exempt)
QBI impact: marginal (QBI is calculated before these personal deductions)

Without year-end planning, tax on $250,000: approximately $55,000 With year-end planning, tax on $211,450: approximately $42,700 Savings: approximately $12,300

Illustrative numbers only, not a real client and not advice for your facts.

When is the planning deadline?

Most strategies require action before December 31:

Equipment must be purchased AND placed in service (not just ordered)
Prepaid expenses must be paid (check written or credit card charged)
Solo 401(k) employee deferrals must be elected by December 31
S-Corp elections for the current year were due by March 15 (for next year, file by March 15)
HSA contributions can be made until the tax filing deadline (April 15)
Solo 401(k) and SEP IRA employer contributions can be made until the tax filing deadline (including extensions)

Related guides:

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Cite this page

Yarik Yarosh, CPA. "Year-End Tax Planning for Small Business Owners: 15 Strategies to Reduce Your Tax Bill." Blue Cloud CPA, September 5, 2026. https://bluecloudcpa.com/guides/small-business-tax-planning-year-end-strategies

This guide is general information, not tax advice for your specific situation. Which points apply, and how, depends on your facts.