Every January, I often hear friends and colleagues express the same regret: “I wish I had known this earlier. I really wish I had known before the end of last year.” Tax planning has a clear deadline, and many of the most effective tax-saving strategies must be completed before December 31. Once the deadline is missed, there is usually no extension, no exceptions, and no chance to start over.
In the past, I was the same: it wasn’t until February, when facing a stack of tax documents, that I started to consider tax issues.
Later, I began working with an accountant. He made me realize that tax planning is not something done only when filing taxes each year, but rather a year-round effort. Especially, some measures taken in the months leading up to the end of the year often have the most significant impact on the final tax burden.
Last year, the following five strategies helped me save a total of $4,800 in taxes. These strategies are not complex, but they all share a common point: action must be taken before the new year arrives.
For most working individuals, this is one of the most effective ways to save on taxes. However, every year, there are still millions of people who do not fully utilize this opportunity.
In 2026, the annual contribution limit for a 401(k) retirement plan is $23,500; if you are over 50 years old, you can also make an additional $7,500 “catch-up contribution.” One significant advantage of a traditional 401(k) is that for every $1 you contribute, your taxable income is usually reduced by $1.
If you haven’t maximized your 401(k) contribution limit, you can check your year-to-date contributions in November and see how much room you have left. Many employers allow employees to adjust their contribution rates mid-year, and some companies even allow additional “lump-sum contributions” in the last few paychecks of the year.
Assuming your marginal tax rate is 24%, increasing your 401(k) contribution to $23,500 could potentially save you $5,640 in federal income tax alone. When adding applicable state income tax, the savings could exceed $7,000. This is real money saved – not deferred payment, not just theoretical numbers, but actual tax dollars you do not have to pay.
If your employer offers a Roth 401(k) option, contributions to a Roth account do not reduce your taxable income for the year. However, the investment growth in the account can grow tax-free in the future, and qualified withdrawals in retirement are typically tax-free. Whether to choose a traditional 401(k) or a Roth 401(k) depends on whether you expect your tax rate to be higher or lower in retirement than it is now. If you are unsure, you can split your contributions between a traditional 401(k) and a Roth 401(k). This can provide you with more flexibility and options in the future.
Individual Retirement Accounts (IRAs) also have their contribution limits. For 2026, the limit is $7,000, and individuals over 50 can make an additional $1,000 catch-up contribution. Whether contributions to a traditional IRA are deductible depends on your income level and whether you participate in an employer-sponsored retirement plan. Contributions to a Roth IRA are not tax-deductible, but investments in the account can grow tax-free. The contribution deadline for both types of IRAs is typically April 15 of the following year. However, by making contributions before the end of the year, the process is simpler and avoids the risk of forgetting amidst year-end busyness.
“Tax-loss harvesting” is one of the most easily overlooked tax-saving strategies in personal investing. The principle is simple: sell investments that have depreciated, turn the paper losses into actual capital losses, and then use these losses to offset capital gains. If losses exceed gains, you can also offset up to $3,000 of ordinary income per year.
If you have stocks or funds in your taxable investment account whose current market value is lower than the initial purchase price, selling them before December 31 can create immediate capital losses that can be used for tax savings. Excess capital losses can usually be carried forward indefinitely for use in future years.
One very important rule to understand is the “wash sale rule”: if you repurchase “substantially identical” investments within 30 days before or after selling the loss-making investment, that loss will not be allowed for tax purposes.
For example, if you sell a losing investment in a fund tracking the S&P 500 index, you cannot repurchase another “substantially identical” fund within the 30-day period. However, you can buy a “total stock market fund” or a similar investment that does not constitute “substantially identical.” This way, you achieve your tax objectives while roughly maintaining your original market exposure.
Last year, by selling a poorly performing international fund, I realized approximately $8,200 in capital losses. I used $5,000 of it to offset capital gains from a real estate investment and the remaining $3,000 to reduce ordinary taxable income. Based on my marginal tax rate, this saved me around $1,980 in taxes. On the day of the sale, I reinvested the funds into another different international fund, thereby keeping the asset allocation of my entire portfolio essentially unchanged.
If you itemize deductions, qualifying charitable contributions can directly reduce your taxable income. Even if you choose the standard deduction, after the increase in the standard deduction amount in 2018, many taxpayers opt for this method, there are still strategies to maximize the tax benefits of charitable giving.
Rather than donating cash, consider donating appreciated stocks directly, which is a very effective strategy. If you hold stocks that have significantly appreciated, donating them to a qualified charity typically allows you to deduct the full market value, while avoiding capital gains tax on the appreciated portion. For instance, if you bought a stock for $2,000 that is now worth $5,000, donating it directly to a charity would allow you to deduct the full $5,000 value and avoid paying capital gains tax on the $3,000 appreciation.
If your annual charitable contributions are not enough to exceed the standard deduction, consider the “bunching” strategy. Simply put, this involves concentrating donations usually made over two or more years into a single year to exceed the standard deduction for that year; in years without bunching, you can opt for the standard deduction. Donor-advised funds make it easier to implement this approach: you can deposit a larger sum of money in the bunching year, receive the corresponding tax deduction, and then distribute the funds to charities according to your plan in the following years.
By employing thoughtful tax strategies with charitable donations, you can turn what was once simple charitable spending into a part of your overall financial plan. The charity ultimately receives the same donation, while you gain some level of tax relief.
If you have a Flexible Spending Account (FSA) for health care or dependent care expenses, the funds in the account typically must be used by December 31; otherwise, they may be forfeited. Some plans allow extended usage until March 15 of the following year, and some plans allow up to $640 of the balance to carry over to the next year, but these rules vary among FSA plans.
You can check your FSA balance in October or November. If there are unused funds in the account, consider scheduling medical appointments, purchasing prescription glasses or contacts, buying eligible over-the-counter medications and medical supplies in advance, or undergoing dental treatments before the deadline.
Contributions to an FSA are typically made pre-tax, meaning these contributions can reduce your taxable income. However, if the money in the account is ultimately forfeited due to not using it within the deadline, this tax advantage is lost. Surrendering funds in your FSA essentially reduces your disposable income. Every year, millions of Americans end up forfeiting these funds because they forget the deadline and miss out on using the money available to them.
In contrast, Health Savings Accounts (HSAs) do not have a “use it or lose it” provision. Funds in an HSA can rollover indefinitely and can even be invested for long-term growth. If your health insurance plan qualifies for an HSA, maximizing your HSA contributions for 2026 – $4,300 for individuals and $8,550 for families – allows you to benefit from the so-called “triple tax advantage”: contributions are tax-deductible, funds in the account grow tax-free, and withdrawals for qualified medical expenses are tax-free.
If you find yourself having to pay a significant amount of tax each year, or receiving a large tax refund annually, this typically means your payroll withholding may not be set appropriately. A large tax bill may result in penalties, while a large tax refund means you’ve essentially been lending interest-free money to the government throughout the year.
Ideally, you should strive to have your annual tax withholding as close as possible to the amount you will actually owe in taxes. You can use the IRS’s Tax Withholding Estimator, have your most recent pay stub ready, and estimate your total annual income. If the estimate shows that your withholding is significantly too high or too low, you can submit a new W-4 form to your employer to adjust the withholding before the final paychecks at the end of the year.
Even adjusting your withholding in November or December can still have a significant impact. If your withholding falls short and you anticipate a large tax bill come tax time, you can increase the withholding in your final paychecks. This can reduce or even eliminate potential penalties for underpayment of taxes. This is because the IRS usually treats withholding as evenly distributed throughout the year, even if all the withholding comes from your December paychecks, the calculation method might still apply similarly.
If there have been significant life changes during the year – such as getting a new job, getting married, getting divorced, welcoming a new child, or buying a home – your withholding is likely in need of adjustments as well. These events can significantly alter your tax situation. Your original withholding settings at the beginning of the year may no longer suit your actual circumstances by the end of the year.
If your annual income exceeds $200,000, you can also consider additional tax-saving strategies. Examples include the qualified business income deduction, Backdoor Roth IRA contributions, the Mega Backdoor Roth strategy implemented through employer retirement plans, and tax planning for the Net Investment Income Tax. These strategies require attention and management before the year-end.
For self-employed individuals, setting up and contributing to a SEP IRA (Simplified Employee Pension Plan) or Solo 401(k) retirement plan before the year-end can allow a significant portion of your income to be directed into a retirement account for tax deferral or deduction. In 2026, for individuals over 50 years old, the total contribution limit through a Solo 401(k) can reach $69,000. For higher-income individuals with successful businesses, this can lead to considerable tax deductions.
The most significant issue I’ve seen is procrastination. Many people are aware of these tax-saving strategies but always wait until December to take action. By this time, brokerage firms are handling a lot of year-end business, payroll departments may be swamped, and charities may not have the time to process your donations promptly.
Therefore, it’s best to start your year-end tax review in October, crunch the numbers in November, and complete the necessary actions by mid-December. Following this timeline, you have enough time to address any potential issues that may arise. Even if unexpected or complex situations come up, you won’t miss out on tax-saving opportunities due to missed deadlines.
Tax planning is not about exploiting loopholes but about using tax law provisions set by Congress sensibly. These provisions are designed to encourage savings, investment, and charitable donations. Every dollar you save in taxes is an extra dollar you can use for investing in and building your financial future. These rules are opportunities for taxpayers, but they only work when action is taken before the deadline.