The best tax planning happens before December 31, not in April. Once the calendar year closes, most of your options for the year close with it — which is why the final weeks of the year are the most valuable time on a business owner's tax calendar. Here are the moves worth reviewing before year-end, several of which are more powerful in 2025 thanks to recent tax-law changes.
This is general information, not individual tax advice — the right moves depend on your specific situation.
Time Your Income and Expenses
If you use the cash method, you have real control over which year income and expenses land in. When you expect to be in the same or a lower bracket next year, the classic move is to defer income into January (delay year-end invoicing) and accelerate deductible expenses into December (prepay for supplies, subscriptions, or services you'll use soon). If you expect a much higher-income year ahead, you might do the opposite. The point is that timing is a lever — use it deliberately rather than by accident.
Buy Needed Equipment Before Year-End
Two provisions make business asset purchases especially attractive right now. 100% bonus depreciation is back and permanent for qualifying assets placed in service after January 19, 2025, letting you deduct the full cost in year one. And the Section 179 expensing cap rose to $2.5 million (with the phase-out beginning at $4 million). The key phrase is "placed in service" — the asset must actually be in use by December 31 to count for this year, so don't wait until the last week if delivery and setup take time.
Maximize Retirement Contributions
Retirement plans are one of the few ways to cut this year's taxes while building your own wealth. Contributing to a 401(k), SEP-IRA, or Solo 401(k) reduces taxable income, and owner-employees can often shelter tens of thousands of dollars. Some plans must be established before year-end even if funded later, so if you don't yet have a plan, this is the moment to set one up rather than discovering the opportunity in March.
Protect Your QBI Deduction
Owners of pass-through businesses can deduct up to 20% of qualified business income under Section 199A — now a permanent provision. Because the deduction phases out at higher incomes and depends on factors like W-2 wages paid, year-end timing of income and expenses can directly affect how much you keep. It's worth a deliberate look before the year closes, especially if your income is near a threshold.
Square Away Estimated Taxes
Your fourth-quarter estimated payment (due in January) is your last chance to avoid an underpayment penalty. Confirm you've met a safe harbor — generally 90% of this year's tax or 100% of last year's (110% if higher-income) — and top up if a strong year pushed your liability higher than you planned. A small catch-up payment now is far cheaper than a penalty later.
Clean Up the Books and the Paperwork
Finally, the unglamorous but essential step: get your books current. Reconcile your accounts, chase down missing receipts, review your accounts receivable for anything genuinely uncollectible, and gather the information you'll need for 1099s. Clean year-end books make every one of the strategies above possible — and make filing in the spring dramatically easier.
How VarStan Helps
Year-end planning is where a good accountant earns their keep, because the window is short and the moves are situational. As a CPA-led firm, we review your numbers before December 31, model the impact of timing decisions and equipment purchases, make sure you're capturing every deduction you qualify for, and keep your books clean so nothing slips through. If you'd rather enter tax season with a plan than a shoebox, that's exactly what we do — and the best time to start is now, not April.