Year-End Tax Moves: A Small Business Owner's Playbook to Cut Your Tax Bill

Most small business owners think about taxes in April. The ones who actually save money think about them in October, November, and December.

That's because by the time the calendar flips to a new year, almost every meaningful tax-saving lever is gone. Equipment purchases, retirement contributions, expense timing, entity elections—nearly all of these have hard deadlines tied to December 31. Wait until tax season and you're not planning anymore. You're just reporting what already happened.

The good news: with a few weeks of intentional planning, most owners can shave thousands off their tax bill using strategies that are perfectly legal, well-documented, and built into the tax code on purpose. Here's how to think about year-end tax planning, what moves to consider, and what mistakes to avoid.

Why the Last 90 Days Matter So Much

The U.S. tax system is built around an annual cutoff. Income earned by December 31 is taxed in that year. Expenses paid by December 31 are deducted in that year. Equipment placed in service by December 31 is depreciated starting in that year.

This creates a narrow window where small timing decisions have outsized financial impact. A piece of equipment bought on December 30 can be fully expensed; the same equipment bought on January 2 sits on your balance sheet until next year. A retirement contribution deposited before year-end can swing your tax bracket; one deposited a week later helps a different tax year entirely.

The point isn't to spend money you wouldn't otherwise spend. It's to time the things you were going to do anyway so they land on the right side of December 31.

Move 1: Time Your Income and Expenses Strategically

If you use cash-basis accounting—as most small businesses do—you can influence when income and expenses hit your tax return based on when cash actually moves.

Defer Income Into the Next Year

If your business is having a strong year and you expect a similar or lower tax bracket next year, consider:

• Delaying December invoices until the first week of January. The work was done in December, but if the cash arrives in January, it's next year's income.
• Holding off on collecting outstanding receivables until the new year, where appropriate.
• Postponing year-end product launches or service deliveries that would generate immediate payment.

Accelerate Deductible Expenses

On the flip side, pull deductible expenses into the current year:

• Prepay rent, insurance premiums, or subscription software for the coming months. The IRS generally allows cash-basis taxpayers to deduct prepaid expenses if the benefit doesn't extend beyond 12 months.
• Stock up on supplies you'd buy in January anyway.
• Pay outstanding vendor invoices before December 31 instead of letting them sit until January.
• Settle credit card charges for business expenses—the deduction happens when the charge is made, not when the card is paid off.

When to Flip the Strategy

If you expect significantly higher income next year (a big contract, a planned price increase, a business expansion), the opposite move makes sense: pull income forward and push expenses out. The goal is always to recognize income in your lower-tax-rate years and deductions in your higher-tax-rate years.

This kind of decision-making depends on accurate, up-to-date books. If your records are three months behind, you're guessing.

Move 2: Maximize Retirement Plan Contributions

Retirement contributions are one of the most powerful—and underused—tax shelters available to small business owners. Done right, they can shift tens of thousands of dollars from taxable income into a tax-advantaged account that grows for decades.

Solo 401(k)

If you're self-employed with no employees other than a spouse, a Solo 401(k) lets you contribute in two roles:

• As an employee: up to $24,500 in 2026 (plus a catch-up if you're 50 or older).
• As an employer: up to 25% of your compensation, with combined limits reaching $72,000 for 2026.

The plan must be established by December 31 of the year you want the deduction, though employer contributions can typically be funded later, up to your tax filing deadline.

SEP-IRA

Easier to set up than a Solo 401(k), a SEP-IRA lets you contribute up to 25% of net self-employment earnings, with the same overall limit ceiling. The major advantage: SEP-IRAs can be both established and funded as late as your tax return due date, including extensions. That gives you breathing room well past December 31.

SIMPLE IRA

Designed for businesses with up to 100 employees, SIMPLE IRAs allow employee contributions up to $17,000 in 2026, with required employer matches. They're cheaper to administer than a 401(k) but cap contributions lower.

The Hidden Tax Credit

Smaller employers starting a new retirement plan can qualify for tax credits worth up to $1,000 per non-highly-compensated employee for the first few years, plus credits for plan startup costs. This effectively makes the first few years of running a retirement plan close to free.

Move 3: Use Section 179 and Bonus Depreciation for Equipment

If your business needs equipment, software, vehicles, or office improvements, year-end is when you decide whether to buy now or wait.

Section 179

For 2026, businesses can immediately expense up to $2.56 million in qualifying purchases under Section 179, with the deduction phasing out once total purchases exceed $4.09 million. Eligible items include:

• Computers, monitors, and office equipment
• Off-the-shelf software
• Machinery and tools
• Office furniture
• Qualifying business vehicles (with weight-based limits)
• Certain improvements to non-residential buildings (HVAC, roofing, security systems)

Bonus Depreciation

For property acquired and placed in service after January 19, 2025, 100% bonus depreciation is back. That means even purchases that exceed Section 179 limits—or businesses with low taxable income—can fully deduct qualifying assets in year one.

The "Placed in Service" Rule

This trips up a lot of business owners: the equipment must be both purchased AND ready for use by December 31. Ordering a server on December 28 that doesn't arrive until January 5 means no current-year deduction. Plan delivery and setup with this in mind.

Vehicle-Specific Limits

If you're buying a business vehicle, weight matters:

• Vehicles under 6,000 lbs: capped at around $12,200 in first-year depreciation
• Heavy SUVs and trucks (6,000–14,000 lbs): up to $31,300 under Section 179
• Vehicles over 14,000 lbs or qualifying work vehicles: no Section 179 cap

This is why you'll see contractors and real estate agents drive specific heavy SUVs—the tax math actually favors them.

Move 4: Contribute to an HSA If You're Eligible

If you're enrolled in a high-deductible health plan, the Health Savings Account is the most tax-advantaged account in the entire code. Contributions are deductible, growth is tax-free, and qualified medical withdrawals are tax-free—a triple benefit no retirement account matches.

For 2026, HSA contribution limits are $4,400 for individuals and $8,750 for families, with an additional $1,000 catch-up if you're 55 or older. Contributions can be made up until your tax filing deadline, but high-income earners often max these out earlier in the year to capture more growth.

Move 5: Reconsider Your Business Structure

Year-end is also a natural time to evaluate whether your business is taxed under the right structure.

Sole Proprietorship to LLC or S-Corp

Once net profit consistently exceeds $60,000–$80,000, the self-employment tax savings of an S-Corp election often outweigh the additional compliance costs. As an S-Corp, you can split income between a "reasonable salary" (subject to payroll taxes) and distributions (not subject to self-employment tax).

LLC vs. C-Corp

C-Corp taxation generally makes sense for businesses planning to retain earnings for growth or seeking outside investment. For most small service businesses, the double-taxation downside outweighs the benefits—but the equation has shifted in industries where the QBI deduction is restricted.

Entity changes typically take effect on the first day of a tax year, so if you're considering a switch, year-end is when you finalize paperwork to be effective January 1.

Move 6: Don't Leave the QBI Deduction on the Table

The Qualified Business Income (QBI) deduction lets eligible pass-through business owners deduct up to 20% of qualified business income. For a sole proprietor, partner, or S-Corp shareholder, this can be one of the largest deductions on the return.

For 2026, the phase-out thresholds are expanding: $75,000 phase-in range for single filers (up to $272,300) and $150,000 for joint filers (up to $544,600). A new minimum $400 QBI deduction also kicks in for taxpayers with at least $1,000 of qualified business income.

If your income is near the phase-out, year-end moves like extra retirement contributions, accelerated expenses, or income deferral can pull you under the threshold and preserve the deduction.

Move 7: Clean Up Bad Debts and Worthless Assets

If you use accrual accounting and you have invoices you've concluded won't be collected, the IRS allows you to write them off as bad debt. The key requirements:

• The debt must have been previously included in income
• You must have made reasonable collection efforts
• The debt must be genuinely uncollectible

Document everything: collection attempts, communications, and the reasoning for writing off the receivable. A clean paper trail is your best defense if questions ever come up.

The same logic applies to obsolete inventory or worthless equipment that's still on your books. Year-end is the time to formally write these off.

Move 8: Make Charitable Contributions That Count

Charitable giving can reduce taxes—but the rules differ by entity type:

• Sole proprietors and single-member LLCs: contributions are personal itemized deductions, only useful if you itemize.
• Partnerships and S-Corps: contributions pass through to owners proportionally.
• C-Corporations: can deduct contributions directly on the corporate return, generally up to 10% of taxable income.

If you're considering a year-end donation, "bunching" multiple years of contributions into a single year (often using a donor-advised fund) can push you over the standard deduction threshold and create a deductible event.

Keep Clean Books So You Can Actually Plan

Every strategy in this guide depends on one thing: knowing where you actually stand financially. You can't decide whether to defer income if you don't know what your income is. You can't decide whether to buy equipment if you don't know your taxable profit.

Most year-end tax surprises come from owners who closed their books in March, looked at the numbers, and realized they could have saved thousands if they'd known a few weeks earlier. Reliable, up-to-date books in November and December turn tax season from a guessing game into a strategic exercise. They also make it dramatically easier for a CPA to give you actionable advice when there's still time to act on it.

Common Year-End Tax Planning Mistakes

Even with good intentions, owners trip themselves up. Watch for these:

1. Spending money to "save on taxes." A $10,000 deduction saves you $2,200–$3,700 in taxes depending on your bracket. Spending $10,000 on something you don't need to save $3,000 isn't a tax strategy. It's a $7,000 mistake.

2. Missing the "placed in service" rule. Ordering equipment in December that doesn't arrive until January gets you nothing for the current year.

3. Forgetting state tax implications. Federal strategies don't always work the same way at the state level. A move that helps your federal return might create a state tax problem.

4. Skipping documentation. Every deduction needs evidence: receipts, bank statements, mileage logs, written collection efforts for bad debts. Verbal or estimated records don't survive an audit.

5. Waiting until the last week. Banks, payroll providers, and retirement plan custodians have cutoffs that come before December 31. A wire that doesn't clear until January 2 is a January 2 transaction.

6. Ignoring next year. Year-end planning is two-sided. Ask not just "How do I save now?" but "What does my tax picture look like next year, and which year benefits more from this deduction?"

A Simple Year-End Tax Planning Calendar

A workable timeline for most small businesses:

• October: Close out Q3 books cleanly. Run a year-to-date P&L and a rough tax projection.
• November: Meet with your CPA. Identify the 3–5 highest-impact moves for your specific situation. Confirm retirement plan elections.
• Early December: Execute equipment purchases, prepay deductible expenses, finalize retirement contributions for plans funded by year-end.
• Late December: Make charitable contributions. Send (or hold) final invoices intentionally. Document everything.
• January: Confirm December transactions hit the books correctly. Begin tax document collection.

Keep Your Finances Organized From Day One

Year-end tax planning works only when you have a clear, real-time picture of your business finances. Beancount.io provides plain-text accounting that gives you complete transparency and control over your financial data—no black boxes, no vendor lock-in, and an audit trail that lives in version control. Get started for free and see why developers, founders, and finance professionals are switching to plain-text accounting to make smarter year-round tax decisions.