RSU Tax Planning: How to Avoid a Surprise Bill at Filing

Restricted stock units are taxed as ordinary income when they vest, and the withholding your employer takes is often lower than what you actually owe. Good RSU tax planning means estimating that gap before each vest, covering it with extra withholding or estimated payments, and deciding in advance whether to sell or hold the shares. This guide walks through each step, with a worked example and a timeline you can follow all year.

TL;DR

• RSUs are generally not taxed when granted. The taxable event is the vest, when shares are delivered and their fair market value counts as ordinary income.
• Employers usually withhold a flat 22% federal rate on supplemental wages (37% above $1 million in a calendar year). For high earners, that is frequently below the real marginal rate.
• The shortfall shows up at filing as a bill, and sometimes as an underpayment penalty. Close it with estimated payments or higher W-4 withholding.
• Selling at vest usually adds little capital gain. Holding adds market risk and a separate capital gains calculation.
• Plan before the vest date, not after. A projection of your full-year income takes less than an hour and removes most surprises.

Table of Contents

• How RSUs are taxed at vesting
• Why withholding is usually not enough
• Estimated taxes and the underpayment penalty
• What to do with the shares after they vest
• A yearly RSU tax planning timeline
• Levers that can reduce the tax on RSU income
• State taxes and working in more than one state
• Our perspective
• Work with The Tax Refinery on RSU income
• FAQ
• Sources

How RSUs are taxed at vesting

An RSU is a promise of company stock that you receive once you meet a vesting condition, usually time with the employer. You pay nothing for the shares. The IRS explains in its equity compensation guidance that RSUs are generally not taxable at grant, and that a taxable event generally does not occur until the RSU vests. For RSUs settled in stock, the rules of IRC §83 apply when the stock is actually transferred to you, which is typically at vesting.

What that means in practice:

• Grant date: nothing to report.
• Vest date: the fair market value of the shares delivered is added to your wages. It is taxed as ordinary income, the same as salary, and it appears on your Form W-2.
• Sale date: any gain or loss after vesting is a separate capital gains event.

Because the vest is treated as pay, it also carries payroll taxes. Social Security tax applies only up to the annual wage base, but Medicare tax has no cap. If you are a high earner, a large vest can also trigger the additional Medicare tax on wages above the statutory threshold for your filing status. Confirm the current thresholds on the IRS website when you project the year.

One point trips up many high earners: RSU income is stacked on top of your salary. A vest that looks like a modest bonus can move the top slice of your income into a higher bracket.

Why withholding is usually not enough

Employers treat RSU income as supplemental wages. According to myStockOptions, employers usually withhold federal income tax at the flat supplemental rate of 22%, or 37% on aggregate supplemental income over $1 million. A payroll explainer on supplemental pay adds that the 37% rate is mandatory above $1 million, even if you have claimed exemption on Form W-4.

The flat rate is a withholding method, not your tax rate. As one equity compensation guide puts it, if RSU income pushes you into the 24%, 32%, 35% or a higher bracket, the 22% withheld can leave a shortfall due at filing.

If you earn above the top of the 24% bracket, the gap is built in. For reference, the 37% bracket begins at a taxable income of $640,600 for single filers in 2026, according to this bracket breakdown. Between 22% and 37% there is a wide range where withholding falls short.

A worked example of the gap

The same guide illustrates the problem with a software engineer who earns a $180,000 base salary and has $170,000 of RSUs vest in the same year. Combined income reaches the 35% federal bracket. The real federal tax on the $170,000 is about $55,500, while roughly $37,400 is withheld at 22%. That leaves a gap of about $18,100, before any state tax or additional Medicare tax.

These figures are an illustration from that guide, not a prediction for your return. Your gap depends on your filing status, deductions, other income and state. The method is what matters:

1. Estimate your full-year taxable income without the RSUs.
2. Add the expected vest value (shares times a realistic share price).
3. Find the marginal rate on the RSU slice, then subtract what will be withheld.
4. The difference is the amount to cover before filing.

How the withholding is collected

The method matters for cash flow. myStockOptions describes two common approaches: net settlement, where the company withholds shares to cover the tax, and sell-to-cover, where enough vested shares are sold to pay the withholding. A separate RSU guide reports that sell-to-cover is the most common, with same-day sale and cash payment as other options.

Either way, you receive fewer shares than the number that vested, but you are taxed on the full value. Keep that in mind when you compare your brokerage statement to your W-2.

Estimated taxes and the underpayment penalty

When withholding falls well short, myStockOptions notes that you may need to pay estimated taxes. There are two ways to close the gap.

Option 1: Raise your paycheck withholding. Withholding from wages is generally treated as paid evenly through the year, no matter when it was actually taken. That makes a Form W-4 adjustment, or an extra amount withheld in the last pay periods, a flexible fix when you find the shortfall late in the year.

Option 2: Make quarterly estimated payments. If a large vest lands in a specific quarter, a payment for that quarter keeps you current. Our guide to safe harbor estimated taxes explains how prior-year and current-year safe harbor targets work, so you can size payments to avoid penalties instead of guessing.

Whichever you choose, write the plan down before the vest. Waiting until you see the W-2 in January leaves you only with the option of paying the balance, plus any penalty.

What to do with the shares after they vest

At vest, your cost basis in the shares equals the value already taxed as income. Later, after you sell, you report the gain or loss on your return. Fidelity's stock plan tax guide states that capital gains treatment depends on whether the sale is short-term (one year or less) or long-term (more than one year).

Selling at vest

When you sell right after vesting, the sale price is close to the vest-date value that was already taxed. Wise's explanation of selling RSUs notes that this typically creates little or no additional capital gain. That makes the tax picture simple: the income tax event is the vest, and the sale adds almost nothing.

Holding the shares

If you hold, any rise above the vest-date value becomes a gain, short-term if you sell within a year and long-term after that. A drop below it becomes a loss.

There is also a concentration question. NerdWallet's guidance on selling RSUs quotes a CFP and CPA who advises selling when RSUs vest, because your salary, unvested shares and vested shares all depend on the same company. Holding is an investment decision on top of a tax decision. Treat it as one: decide the percentage you are comfortable holding before the vest, then follow the rule.

Using losses carefully

If you hold and later sell at a loss, capital losses can offset capital gains and, for unused losses, up to $3,000 of ordinary income, per Fidelity's rules for selling company shares. The same source warns that a wash sale can disallow a loss when company shares are bought within 30 days before or after the loss sale. Because new RSUs vesting on a regular schedule can count as acquisitions, check your vest calendar before you harvest a loss on company stock.

A yearly RSU tax planning timeline

High earners do best with a repeatable calendar. Here is a practical version:

That last step is a common source of overpaid tax. If your broker reports a basis that excludes the income you already recognized at vest, the sale can look like a larger gain than it was. Correct the basis when you file.

Levers that can reduce the tax on RSU income

RSU income itself is ordinary wages, so you cannot change its character. You can change the income around it.

• Retirement contributions. Maximizing pre-tax contributions in a vest year lowers taxable income at your highest marginal rate.
• Charitable giving. Bunching donations into a vest year, or giving appreciated shares you have held long term, can be more efficient than writing a check. Confirm the deduction rules for your situation with a tax professional.
• Timing. Where your plan allows, knowing which tax year a vest falls in helps you balance income between years. A vest in early January lands in a different year than one in late December.
• Business income. If you also own a business, your entity structure and deductions change how much of your income lands in the top brackets. Our high earner tax planning guide covers how these pieces fit together.

State taxes and working in more than one state

State income tax is also withheld at vest where it applies, and the rates and rules differ. myStockOptions notes that applicable state and local taxes are withheld at vesting. A state with no income tax withholds nothing, while a high-tax state can withhold a good deal.

If you moved, or you work remotely for an employer in another state, the income may be taxable in more than one place. RSUs are often sourced based on where you worked between the grant and the vest. Remote workers should read our guide on remote employee state taxes and convenience rule audits before a vest year. If you live in the Pacific Northwest or Idaho, confirm your state's treatment of equity pay with a preparer who handles both states.

Our perspective

Most RSU surprises are not caused by the shares. They are caused by timing. A client sees a vest in March, a W-2 in January, and a balance due in April, with nothing in between that connected the three.

We build RSU planning into the same projection we use for every high-earning client. We estimate the year's income before a vest, size the withholding gap, and set the payment that closes it. Then we revisit the numbers after each vest, because share prices and bonuses move the answer.

The owners and professionals we serve rarely have RSUs alone. They have a spouse's income, a rental, a practice or an S corporation. The right move on the RSU side depends on all of it, which is why we prefer year-round advisory over a once-a-year filing. Planning is where the money is kept, and it is rarely visible on a return that has already been filed.

Melissa

Work with The Tax Refinery on RSU income

If RSUs sit alongside business income, rentals or a practice, a one-time return will not catch the interactions. We offer ongoing tax advisory built around a projection of your full year. Our Quarterly Tax Strategy Sessions are $9,497 per year, and Monthly Tax Advisory is $11,997 per year. Both are described on our tax strategy comparison page.

If you own an S corporation and want to set up planning around it, our S-Corp Tax Strategy Accelerator is $997. For return preparation only, see our published fee schedule. If you already run an S corporation, our S corp tax planning guide shows how that structure fits with W-2 equity income in the same household.

FAQ

Are RSUs taxed when they are granted?

Generally no. The IRS says RSUs are generally not taxable at grant, and the taxable event generally does not occur until they vest. At that point, the fair market value of the delivered shares is reported as ordinary income.

Why is my RSU tax bill higher than what was withheld?

Employers usually withhold a flat 22% federal rate on supplemental wages, which is a withholding method and not your actual tax rate. If your total income places the RSU slice in the 32%, 35% or 37% bracket, the difference is due at filing. Projecting your income before the vest shows the size of the gap.

Should I sell my RSUs as soon as they vest?

Selling at vest usually adds little or no capital gain, because the sale price is close to the value already taxed. It also reduces the concentration risk of having your pay and your savings tied to one company. Whether to sell is a personal decision, so set a written rule before the vest and talk with your advisor about your situation.

Do I need to make estimated tax payments on RSU income?

Possibly. If withholding is substantially lower than what you will owe, estimated payments can cover the difference. You can also raise withholding on your paycheck late in the year. Review the safe harbor rules to avoid an underpayment penalty.

Sources

• IRS Publication 5992, equity compensation guidance
• myStockOptions: how taxes are withheld from restricted stock
• myStockOptions: will withholding cover the tax owed
• Supplemental pay explainer
• RSU tax withholding guide
• How RSU taxes work
• Fidelity stock plan tax guide
• Fidelity rules for selling company shares
• Tax implications of selling RSUs
• NerdWallet: sell or hold RSUs
• 2026 federal tax brackets

Recommended

• Year-Round Tax Planning: A Quarterly Guide for Owners
• Year-End Tax Planning: Your December Checklist
• Safe Harbor Estimated Taxes: Rules for Self-Employed Filers