Expecting a bonus, stock compensation or property sale in 2026? Check your withholding before a surprise tax bill in 2027

The last few months of the year can bring a change in income that was not part of their usual paycheck.

Maybe you are expecting a year-end bonus. Perhaps some restricted stock units (RSUs) are about to vest. Or you could be selling a property and realizing a capital gain.

Any of these events can affect your 2026 tax picture. That makes it worth taking a look at how much federal tax you have already paid and whether your withholding or estimated payments are keeping up.


The federal tax system generally works on a pay-as-you-go basis. In other words, taxes are typically paid as income is received through paycheck withholding, estimated tax payments or both. If you have not paid enough during the year, you could end up owing money when you file your return and may face an underpayment penalty in some cases.

Getting a Bonus? Your Employer May Withhold 22%

The IRS treats bonuses as supplemental wages, which have their own withholding rules.

For 2026, an employer can generally use a flat 22% federal income tax withholding rate when qualifying supplemental wages are paid separately from regular wages. Employers can also use another calculation method in certain situations, so not every bonus will necessarily have exactly 22% withheld.

There is a separate rule for employees who receive more than $1 million in supplemental wages from an employer during the year. The amount above $1 million is subject to 37% federal income tax withholding.

One thing to keep in mind: the amount withheld from your bonus is not necessarily the amount of tax you ultimately owe on it. Withholding is simply money paid toward your federal tax bill. Your final tax liability is determined when you file your return.

An RSU Vest Can Add to Your Taxable Income

RSUs can create another tax event when they vest.

Fidelity says RSUs are generally taxed when they vest, with the value of the shares generally treated as ordinary compensation income. Taxes are generally withheld at that point, although the way the withholding is handled depends on the stock plan.

For example, shares can be withheld or sold to cover the tax obligation.

The tax picture can change again if you later sell the shares. Depending on the sale price and your tax basis in the shares, the transaction can result in a capital gain or loss.

Selling a Property? The Tax Impact Depends on the Sale

A property sale can also affect your taxes if it results in taxable income or a capital gain. One type of income that may result in an estimated-tax liability when not enough tax has been paid through withholding or other payments is capital gains. But selling a property does not automatically mean you will have to make an estimated tax payment.

The IRS generally requires estimated tax payments when a taxpayer expects to owe at least $1,000 after accounting for withholding and refundable credits, and the amount paid during the year falls below the applicable threshold.

The timing of the income can also matter, for taxpayers who receive a large capital gain during the year, the IRS provides an annualized income installment method in certain situations. This can take into account the fact that income may not arrive evenly throughout the year.

What to Check Before the End of 2026

If your income has changed this year, then a quick review of your tax payments could help you get a better idea of where you stand.

Look at:

• Federal income tax already withheld from your paychecks
• Any bonus you expect to receive
• RSUs scheduled to vest
• Capital gains you expect from a property or other asset sale
• Estimated tax payments you have already made
• Your expected income and tax liability for 2026

The IRS has a Tax Withholding Estimator that can help taxpayers review their withholding. If you decide your paycheck withholding needs to change, you can generally submit a new Form W-4 to your employer.

If you have income that is not fully covered by withholding, the IRS also provides rules for estimated tax payments and their applicable deadlines.

Why a Year-End Tax Check Can Be Worth It

Getting a bonus, watching RSUs vest or selling a property does not automatically mean you will be hit with a large tax bill when you file your 2026 return.

But extra income can change your overall tax liability. Checking your withholding and estimated payments before the year ends can give you a clearer picture of whether you have paid enough so far.