Most of your tax bill is decided long before you file. By the time a return is due in April, the year that created the liability has already closed, and the best moves are off the table. That is why year-end tax planning matters so much for high earners. The weeks before December 31 are the last stretch where you still control real levers: how much you contribute, when income lands, and which deductions you claim. This guide walks through the moves that carry the most weight for someone earning $250,000 or more, and how to sequence them before the calendar runs out.
Why the window closes on December 31
The federal income tax runs on a calendar year for individuals. In general, an action only counts for the current year if it happens by December 31. Contribute to your 401(k) after that date, and the deduction belongs to next year. Sell a loser on January 2, and the loss cannot offset this year’s gains. A few items, such as IRA and HSA contributions, allow a grace period into the April filing deadline, but most planning moves are locked to the calendar.
This deadline is also what separates planning from filing. Filing simply records what already happened. Planning changes the outcome while there is still time to act. For a high earner facing a top marginal rate near 37%, plus a possible 3.8% surtax on investment income, small timing decisions in December can translate into thousands of dollars. The moves below are where that value tends to concentrate.
Fund every tax-advantaged account you can
The simplest year-end win is also the one people most often leave on the table: filling the accounts that reduce taxable income or grow tax-free. Contribution limits reset each year, and unused room does not carry forward. If you have not maxed your accounts by late fall, this is where to start.
The table below shows the key 2026 limits for the accounts high earners use most. Payroll-based plans like the 401(k) generally must be funded through withholding by December 31, so adjust your remaining paychecks now if you are short.
| Account | 2026 limit | Year-end note |
|---|---|---|
| 401(k), 403(b), 457 employee deferral | $24,500 | Add a catch-up if you are 50 or older; fund through payroll by December 31. |
| Total 401(k) additions (employee plus employer) | $72,000 | Relevant for after-tax and mega backdoor Roth contributions. |
| Traditional or Roth IRA | $7,500 | You have until the April filing deadline, but confirm income limits first. |
| Health savings account (family) | Set annually by the IRS | Requires a qualifying high-deductible plan; triple tax advantage. |
For W-2 earners who are already over the Roth income limit, the backdoor and mega backdoor Roth routes remain open, and both are worth reviewing before year-end. We cover the full set of options in our guide to how high-income W-2 earners can legally reduce their taxes. If you own a business, the ceiling is far higher, and we return to that below.
Time your income and your deductions
After funding accounts, the next lever is timing. The core idea is straightforward. If you expect to be in a lower bracket next year, push income forward and pull deductions into this year. If you expect a higher bracket next year, do the reverse. High earners with variable pay, bonuses, or business income often have more room to steer this than they realize.
When it makes sense to defer income
Deferring income moves a taxable event into a future year, ideally one where your rate is lower. An executive might elect to push a bonus into next year, or a consultant might delay a December invoice so payment arrives in January. Business owners on the cash method have particular flexibility here, since income is generally taxed when received. The caveat is that deferral only helps if next year’s rate is truly lower. Pushing income into a year when you expect a raise or a liquidity event can backfire.
Accelerating and bunching deductions
On the deduction side, the opposite logic applies. Paying a deductible expense before December 31 claims it this year. Because the standard deduction is high, at $32,200 for married couples filing jointly in 2026, many high earners no longer itemize every year. Bunching solves that. You concentrate two years of deductible items, such as charitable gifts and certain state and local taxes up to the cap, into a single year so the total clears the standard deduction. In the off year, you take the standard deduction instead. Over a two-year cycle, the same dollars produce a larger combined benefit.
Harvest losses and manage your gains
Investment moves are among the most reliable year-end tools, because you control exactly when a gain or loss is realized. Tax-loss harvesting is the practice of selling a position that has dropped below its purchase price to lock in a capital loss on purpose. That loss offsets capital gains you have taken elsewhere, and up to $3,000 of any excess can offset ordinary income, with the rest carried forward. For a high earner who rebalances a taxable account or sells appreciated stock, the savings can be meaningful.
The trap to avoid is the wash sale rule, which disallows the loss if you buy the same or a substantially identical security within 30 days on either side of the sale. The usual fix is to buy a similar but distinct fund so you stay invested without breaking the rule. We walk through the mechanics and the pitfalls in our guide to tax-loss harvesting. December is also the time to review whether to realize long-term gains in a lower-income year, since the long-term rate is generally 0%, 15%, or 20% rather than the ordinary rates that hit short-term gains.
Make your charitable giving work harder
If you give to charity, the way you give often matters more than the amount. Writing a check is the least efficient method for someone with appreciated investments. Instead, consider these year-end approaches, each of which must be completed by December 31 to count for the current year.
- Donate appreciated stock. Giving a security you have held more than a year generally lets you deduct the full fair market value and skip the capital gains tax you would owe on a sale. The charity receives the same value, and you remove an embedded gain from your books.
- Use a donor-advised fund. A donor-advised fund lets you make one large, deductible gift now and recommend grants to charities over future years. It pairs naturally with the bunching strategy above, letting you concentrate several years of giving into a single high-income year. Our guide to charitable bunching with a donor-advised fund shows how the two work together.
- Consider a qualified charitable distribution. If you are at least 70 and a half and hold an IRA, you may be able to give directly from the account, which can satisfy a required distribution without adding to taxable income.
Keep contemporaneous records for every gift. For noncash donations above certain thresholds, the substantiation rules are strict, and a missing acknowledgment can cost you the deduction.
Year-end moves for business owners
Business owners have the widest set of levers, and several of them expire at year-end. Because the 2025 tax law made 100% bonus depreciation permanent, a company that buys and places qualifying equipment in service by December 31 can generally deduct the full cost this year rather than depreciating it over time. The phrase that matters is placed in service, not merely ordered, so delivery and installation timing count.
Retirement plans offer even larger numbers. A solo 401(k) or a defined benefit plan can shelter far more than an employee deferral alone, and some plans must be established before year-end even if funding happens later. Owners in high-tax states should also review the pass-through entity tax, a legal workaround to the federal cap on state and local tax deductions that generally requires the entity to make or elect the payment on a set schedule. Finally, review reasonable compensation, accountable plan reimbursements, and any bonuses to family employees before the books close. Each of these is a defined strategy in its own right, and each is easier to execute with weeks to spare than in the final days of December.
A year-end planning checklist
Use the sequence below as a working checklist. Move through it in order, since the earlier items often inform the later ones.
- Project your taxable income for this year and your likely bracket for next year. The gap between them drives most timing decisions.
- Maximize 401(k) and other payroll-based contributions through your remaining paychecks.
- Confirm IRA, HSA, and any backdoor Roth steps, and complete anything tied to December 31.
- Review your taxable portfolio for losses to harvest and gains to manage, watching the wash sale window.
- Plan charitable gifts, ideally with appreciated assets or a donor-advised fund, and gather documentation.
- For business owners, place equipment in service, fund or establish retirement plans, and address the pass-through entity tax.
- Check whether a fourth-quarter estimated payment is needed to avoid an underpayment penalty.
- Review the results with a licensed tax professional before you execute anything irreversible.
Common year-end mistakes to avoid
Even careful people stumble in December, usually by rushing. A few errors show up again and again. First, letting the tax tail wag the investment dog: selling a good position purely for a loss, or holding a bad one to defer a gain, can cost more than the tax it saves. Second, missing the placed-in-service rule and assuming an ordered asset qualifies. Third, triggering a wash sale through an automatic reinvestment in another account. Fourth, forgetting the estimated-tax deadline and absorbing a penalty that careful planning would have avoided.
The larger mistake is treating year-end as the whole plan. The best outcomes come from decisions made across the year, with December used to confirm and finish rather than to scramble. Reactive filing captures none of this, which is the difference proactive planning is built to close.
Frequently asked questions
When is the real deadline for year-end tax moves?
For most actions, it is December 31. Selling investments, funding a 401(k) through payroll, placing equipment in service, and completing charitable gifts all must happen by then. IRA and HSA contributions are the main exceptions, since you generally have until the April filing deadline, but confirm the rules for your situation.
Does year-end planning only help business owners?
No. Business owners have more levers, but W-2 earners can still fund retirement accounts, harvest losses, time bonuses where the employer allows it, and give strategically to charity. In many cases the biggest W-2 savings come from maximizing tax-advantaged accounts and managing capital gains before December 31.
Should I make a fourth-quarter estimated payment?
Possibly. If you have had a large gain, a bonus, or business income without enough withholding, a January estimated payment can reduce or eliminate an underpayment penalty. Whether you owe one depends on your total withholding and safe-harbor position, so check your numbers before the deadline.
Your next step
Year-end tax planning rewards people who start early and finish deliberately. Begin by projecting your income and bracket, then work through the checklist above while there is still time to act. The goal is not a last-minute scramble in the final week, but a short list of confirmed moves you complete with room to spare.
For more strategies you can put to work this year, download our free guide, Top 5 Tax Strategies for High-Income Earners. When you are ready for the full framework of more than 100 strategies, explore the ETS Playbook. For the official figures, the IRS confirms the 2026 retirement limits in its announcement of the 2026 contribution limits, and it explains the fourth-quarter rules in its overview of estimated taxes.
The strategies described here are general educational information about the U.S. tax code. Individual results vary based on income, entity structure, state law, and other factors. This is not personalized tax, legal, or financial advice. Consult a licensed tax professional before implementing any strategy.
