What Year-End Tax Moves Should Business Owners Make Before December 31?

by Chris Clepp | October 6, 2026

By Christopher Clepp, ChFC®  ·  Building Towards Wealth

What Year-End Tax Moves Should Business Owners Make Before December 31?

Year-end tax moves are the moves you can no longer make after January 1. For business owners, the highest-leverage decisions usually involve retirement plan funding, equipment timing, charitable giving, and how income and expenses land across the calendar.

Every year the same thing happens. The calendar flips to December, owners look up from running their businesses, and the scramble begins: buy something, fund something, give something, quick, before the ball drops. Some of that scrambling helps. A lot of it burns cash to feel productive.

So here’s the calm version: the year-end moves that tend to matter for business owners, roughly in order of leverage, with the honest math on each. Work this list in November if you can. December works too, but November gives your CPA time to think instead of react.


Retirement funding: fast-twitch and slow-twitch

The retirement plan question splits into two piles: what has to happen by December 31, and what can wait until you file.

Must do by Dec 31
Fast-twitch: Employee deferrals

2026 limits: $24,500 deferral, +$8,000 catch-up (age 50+), +$11,250 catch-up (age 60–63). These elections run through payroll. Miss December and the room is gone.

Can wait until filing
Slow-twitch: Employer contributions

Profit sharing and defined benefit funding can typically be made up to the return filing deadline, extensions included. Combined 415(c) cap: $72,000 for 2026.

The common mistake: rushing profit-sharing numbers in December that could wait until spring, while leaving deferral room on the table that expires at midnight on the 31st. Know which pile each move is in, and confirm with your plan administrator — plan documents can be more restrictive than the IRS.

Section 179, bonus depreciation, and the truck math

Equipment timing is one of the few year-end moves with real discretionary dollars attached, and it’s also where the worst December decisions get made.

Section 179 (2026)
Immediate expensing up to $2,560,000. Phase-out begins above $4,090,000 of property placed in service.
Bonus depreciation
100% bonus depreciation restored for qualifying property under current law. If the business needs the equipment, placing it in service before year-end pulls the deduction into this year.

The truck math: A $50,000 truck at a 37% marginal rate saves $18,500 in tax. The truck still costs you $31,500 in real cash. If the business needs the truck, buy it. If it doesn’t, you traded $31,500 for a parking spot. Spending a dollar to save 37 cents has never been a strategy. Timing a purchase you were making anyway is.

“Casual cash giving got less tax-efficient for high earners in 2026. Deliberate structure got more valuable. The gap between the two is real dollars.”

Charitable giving with a brain

Year-end is when most charitable dollars move, and 2026 changed the rules in ways worth knowing before you write the checks. Itemizers can now deduct charitable contributions only above a floor of 0.5% of adjusted gross income, and the value of the deduction is capped for those in the top bracket. The net effect: casual cash giving got less tax-efficient, and structure got more valuable.

Donor-advised fund
Bunch several years of giving into a DAF in a high-income year. Clears the new floor, takes the deduction now, grants flow to charities on your schedule. See Donor Advised Funds: A Flexible Solution for Charitable Giving.
Appreciated stock
Donating appreciated stock instead of cash removes the embedded capital gain while the charity receives full value. Giving from cash while appreciated stock sits in a taxable account costs real money.
QCDs (age 70½+)
Up to $111,000 per person in 2026 goes straight from the IRA to charity, excluded from income entirely and untouched by the new floor.

Income and expense timing

For owners with discretion over when revenue lands and when expenses get paid, December is when the choices have teeth.

  • Cash-basis businesses can pay January’s vendors in December and defer billing where contracts allow.
  • Accrual-basis businesses have less room but still control bonus accruals and certain prepaid expenses.
  • S-Corp owners have flexibility on distribution timing.
One caution: these moves only work when the timing is real. Deducting an expense that hasn’t been incurred, or deferring income you’ve economically earned, crosses the line from planning into trouble. Timing games that exist only on paper are how a clean return becomes an interesting one, and you never want an interesting return.


The five mistakes that cost the most

After enough Decembers, the expensive mistakes start to rhyme.

1
Letting income drift past the QBI phase-out when a deductible retirement contribution could have preserved the deduction. QBI became permanent under the 2025 tax law — protecting it is now an annual project. See What Tax Deductions Do Business Owners Miss Every Year?
2
Missing safe harbor on quarterly estimates and paying a penalty one well-timed Q4 payment would have erased.
3
Implementing a Roth conversion in late December without knowing where the year’s bracket landed. See Should I Do a Roth Conversion This Year?
4
Forgetting 1099 obligations on contractors until the penalties compound.
5
Buying equipment for the deduction instead of the business. See the truck math above.

The cleanest year-end is the one with the fewest surprises. For the fuller checklist that sits around these moves, Year-End Financial Planning: Your Ultimate Guide walks the broader ground.

Let’s talk

If your year-end tax planning has historically been a December scramble, the fix is a November conversation inside a plan that runs all year. That’s how I work with business owners through the Abundant Wealth Process.

Schedule a Call

Disclosure: This article is provided for general educational and informational purposes only and is not personalized tax, legal, accounting, or investment advice. Examples involving dollar amounts are hypothetical and illustrative only; individual results vary based on specific circumstances. Tax laws and IRS thresholds change frequently; 2026 figures cited above reflect IRS-published limits as of this writing and should be verified before reliance. Christopher Clepp, ChFC®, is a financial advisor and not a CPA or attorney; consult with qualified tax, legal, and accounting professionals regarding the application of any strategy to your specific situation. References to internal blog content are educational only and do not constitute a solicitation.

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