10 Tax Strategies Before December 31st - Strategic Tax Planning Blog
Tax Strategy December 10, 2025 8 min read

10 Tax Strategies You Must Implement Before December 31st

The clock is ticking. These proven strategies can save business owners and high-income earners thousands—but only if you act before year-end.

A professional woman is sorting through tax documents, highlighting her role in tax preparation and analysis in a contemporary office setting.

Why This Matters: Most tax-saving strategies must be implemented BEFORE December 31st. Once the calendar flips to January 1st, your opportunities for the previous tax year are gone forever. Here's what you need to know right now.

1. Accelerate Business Expenses

If you're planning major purchases for early next year, consider moving them to December instead. Equipment, software, supplies, and other deductible business expenses can reduce your taxable income for the current year.

Action Items:

  • Review planned Q1 purchases and move eligible items to December
  • Pay outstanding vendor invoices before year-end
  • Prepay 2026 business expenses (insurance, subscriptions, etc.)

2. Maximize Retirement Contributions

Retirement plan contributions are one of the most powerful tax-saving tools available. For 2025, contribution limits are substantial—but you must make contributions by December 31st for them to count toward this year's taxes.

2025 Contribution Limits:

  • 401(k): $23,000 (plus $7,500 catch-up if over 50)
  • SEP IRA: Up to 25% of compensation or $69,000
  • Solo 401(k): $69,000 total ($76,500 with catch-up)
  • Traditional IRA: $7,000 ($8,000 with catch-up)

3. Defer Income to Next Year

If you're on the cash basis (most small businesses), you have control over when you recognize income. Consider delaying December invoicing until January 1st, so that income hits your 2026 tax return instead of 2025.

Important: This strategy is most beneficial if you expect to be in a lower tax bracket next year. If your income will jump significantly in 2026, you may want the opposite approach.

4. Harvest Investment Losses

Tax-loss harvesting allows you to sell investments at a loss to offset capital gains. You can deduct up to $3,000 in net capital losses against ordinary income, and carry forward additional losses indefinitely.

Pro tip: You can immediately buy a similar (but not identical) investment to maintain your market position while capturing the tax loss. Just be aware of the wash-sale rule (30-day waiting period for identical securities).

5. Make Charitable Contributions Strategically

Year-end is prime time for charitable giving—but there are smarter ways to donate than writing a check. Consider these advanced strategies:

Donate Appreciated Stock

Avoid capital gains tax while getting a deduction for the full fair market value

Donor-Advised Fund

Get an immediate deduction while distributing funds to charities over time

6. Review Your Business Entity Structure

If you're operating as a sole proprietor or single-member LLC, you might be paying significantly more in self-employment taxes than necessary. Converting to an S-Corp can save thousands annually, but it must be done strategically.

Potential Savings Example:

Business profit: $150,000

Sole Proprietor:

~$21,200

in self-employment tax

S-Corp (with strategic salary):

~$9,600

in employment tax

Potential annual savings: $11,600+

7. Take Advantage of Section 179 and Bonus Depreciation

Section 179 allows you to immediately deduct the full cost of qualifying equipment purchases (up to $1.22 million for 2025) instead of depreciating them over several years. Bonus depreciation adds even more opportunity.

Qualifying Assets Include:

  • Computers and software
  • Office furniture and fixtures
  • Machinery and equipment
  • Business vehicles (with limits)
  • Certain property improvements
  • Off-the-shelf software

8. Pay Yourself a Year-End Bonus

If you're a C-Corp owner, consider paying yourself a performance bonus before year-end. This shifts income from the corporation (taxed at 21%) to you personally, where it can potentially be taxed at a lower effective rate after deductions.

For S-Corps and partnerships, consider year-end distributions to take advantage of current tax rates before potential increases.

9. Review and Adjust Estimated Tax Payments

If you had a great year and your estimated payments are too low, you'll owe underpayment penalties. Make a final estimated payment before December 31st to minimize these penalties.

Penalty Trigger: If you owe more than $1,000 at tax time and haven't paid at least 90% of your current year tax liability (or 100% of last year's), you'll face penalties.

10. Document Everything

This isn't glamorous, but it's crucial. Before year-end, organize your receipts, invoices, mileage logs, and business expense documentation. An IRS audit can disallow deductions you can't substantiate—even if they were legitimate business expenses.

Key Documentation to Review:

  • All business expense receipts (digitize and organize by category)
  • Mileage logs with dates, destinations, and business purposes
  • Meal and entertainment expenses with attendees and business discussed
  • Home office measurements and usage percentages
  • Contracts and agreements showing business relationships

The Bottom Line: Don't Wait

These strategies are powerful—but only if you implement them before December 31st. Once the calendar flips to January 1st, most of these opportunities are gone for good.

The difference between reactive tax preparation and proactive tax strategy is often tens of thousands of dollars. Business owners who plan ahead keep more of what they earn.

Need Help Implementing These Strategies?

Our team specializes in strategic tax planning for business owners and high-income earners. We'll analyze your situation and create a customized strategy to minimize your tax burden legally and ethically.

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