Year-End Tax Planning Checklist
Effective year-end tax planning requires systematic review of business income, deductions, and strategies by early December. A comprehensive checklist ensures you capture all available tax-saving opportunities before December 31 deadlines. Business owners implementing year-end planning strategies typically save $15,000 to $50,000 in federal taxes compared to those who wait until April tax filing.
Income Projection and Bracket Analysis
Calculate anticipated year-end income from all sources. Project total taxable income and identify which tax bracket you'll fall into. If income is approaching a higher bracket threshold, strategies to reduce income (retirement contributions, charitable donations, accelerated business deductions) may provide marginal benefit. Run projections through December to identify optimal year-end income level.
Retirement Plan Contributions
Contribute to Solo 401(k), SEP-IRA, or traditional IRA before December 31. Solo 401(k) contributions up to $69,000 (2024) reduce taxable income dollar-for-dollar. SEP-IRA contributions up to 20% of net self-employment income reduce AGI above-the-line. These contributions have December 31 deadlines; January contributions don't qualify for current-year deduction.
Equipment Purchases and Depreciation
Equipment purchased before December 31 qualifies for depreciation in the current year. Items costing under $5,000 are expensed immediately (Section 179). Larger equipment qualifies for bonus depreciation (100% in 2025, declining 2026+) or regular MACRS depreciation. Planned December equipment purchases accelerate deductions into the current year.
Charitable Contributions
Cash donations made by December 31 are deductible in the current year. Appreciated securities donations (avoiding capital gains tax) are deductible at fair market value. For donors in high income years considering bunching charitable giving, make concentrated contributions in high-income years and reduced contributions in lower-income years.
Business Expense Acceleration
Discretionary business expenses (office supplies, professional services, subscriptions) made before year-end are deductible in the current year. Review planned expenses and accelerate non-essential costs into the current year if you're running higher income than anticipated. Defer essential expenses to January if you anticipate lower income next year.
Estimated Tax Payment Review
Calculate total estimated tax payments made during the year. If withholding and estimated payments are insufficient (likely to be less than 90% of current year or 110% of prior year tax), make a large fourth-quarter estimated payment (or income tax withholding adjustment) by December 31 to avoid underpayment penalties.
Investment Loss Harvesting
Review investment portfolios for realized losses. Sell underperforming investments to harvest losses, offsetting capital gains and up to $3,000 in ordinary income. Remaining losses carry forward. Tax-loss harvesting can offset $20,000 to $100,000+ in investment gains annually.
Passive Activity Loss Position
Review passive activity loss position. If you have suspended losses from prior years, confirm you qualify for Real Estate Professional Status (REPS) in the current year. REPS qualification allows deduction of all suspended passive losses in the qualification year. Confirm 750+ hours in real estate activities and 50%+ allocation to real property work.
S-Corporation and Partnership Elections
Deadline for electing S-corporation status for C-corporations is December 31 of the year preceding the election (if you want the election effective January 1 of the current year). For current-year elections, December 31 may be too late. Verify election status with your tax advisor to ensure proper classification for current and next year.
Estimated vs. Actual Expense True-Up
If you've been using estimated business expenses (estimated vehicle mileage, home office, depreciation), reconcile to actual expenses by year-end. Correct estimates that exceeded or fell short of actual amounts. Maintain contemporaneous documentation (mileage logs, receipts) to support deductions claimed.
Business Debt and Interest Deduction
Review business debt outstanding. Interest paid on business debt is deductible. If you're approaching interest deduction limitations (Section 163(j) for high-leverage businesses), confirm limitations calculation and plan adjustments for next year if needed.
Action Items - December Priority List
1. Calculate year-end income projection by November 30. 2. Identify tax bracket and marginal tax rate. 3. Calculate retirement plan contribution room and deadline. 4. Review equipment purchase plans; execute pre-December 31. 5. Accelerate discretionary business expenses if needed. 6. Review and harvest investment losses. 7. Confirm estimated tax payment sufficiency. 8. Make final estimated payment if needed by December 31. 9. Verify S-corporation and partnership election status. 10. Reconcile expenses and mileage logs to actual.