You just got an RSU grant. Or a tranche vested last month.
Either way, you’re wondering the same thing: is this actually free money, or is the IRS about to take a third of it before you see a cent?
Both. And if you don’t plan ahead, the bill appears in April without warning.
What are the RSUs?
Conceptually, your employer promises you shares — but only delivers them once you satisfy a condition. This condition is generally the “time”. Stay 4 years, receive all the shares. Leave in year 2, forfeit the rest.
Before vesting, an RSU is worth exactly 0 dollars. Think of it as the employer presenting a transparent safe filled with cash, along with a countdown timer. It is possible to see the money inside, but you cannot touch it. That’s the grant.
When the timer hits 0 and the door opens — that’s vesting. And the IRS is standing right next to the safe. The exact second it opens, they calculate what’s inside & demand their cut.
The RSU tax timeline
| Event | When | Taxed? | Tax Type | What’s Taxed |
| Grant | Awarded by employer | No | None | N/A |
| Vest | Shares become yours | Yes | Ordinary Income | Full market value on vest date |
| Sale < 1 yr | Sold within 12 months | Yes | Short-Term Capital Gains | Profit above vest price |
| Sale > 1 yr | Sold after 12 months | Yes | Long-Term Capital Gains | Profit above vest price, lower rate |
The Vest: where the real tax comes
When your shares vest, the IRS treats the total market value exactly as if the employer handed you a cash bonus on the regular paycheck. It is taken into consideration as “income”. Period.
Let’s assume 1,000 RSUs vest when the stock is at USD 50:
1,000 × 50 = USD 50,000 added to the taxable income for the year
That 50k lands on the W-2. It gets taxed at the marginal rate. This happens whether you sell the shares immediately or hold every single one.
The Under-Withholding Trap
Most brokerages withhold RSU taxes at the IRS supplemental rate of 22%. That sounds adequate. It isn’t — not for most tech or corporate employees.
If the total income puts you in the high earner, 32% or 35% bracket, the brokerage just withheld 10–13% less than actually owed. On a USD 50,000 vest, that’s a USD 5,000–6,500 gap. Waiting there quietly until April.
Fixing it now: calculate the real marginal rate and subtract 22%, then multiply by the vest value. Move that exact amount into a separate account the day shares land. Consider quarterly estimated payments if the vests are large or frequent.
The sale — the second tax event
After vesting, the shares behave like any stock purchased on the open market. Any price appreciation from that point is a capital gain — not ordinary income.
The easiest way to recognize this:
Imagine the employer gives you a USD 50,000 house. You pay income tax on that gift immediately. A year later, you sell it for USD 60,000. The IRS doesn’t touch the full USD 60,000 — you already paid on the house. They only tax the USD 10,000 profit from the flip. That’s the real capital gain.
Back to the RSU example. You hold your vested shares 15 months and sell at USD 60:
- Cost basis (vest price): USD 50,000
- Sale proceeds: USD 60,000
- Taxable gain: USD 10,000 — at the long-term rate
Sell before 12 months? Same gain, ordinary income rates. The 12 month line is one of the most financially concrete dates on your calendar.
Smart 4 actions that protect your position
1. Model your vest year before it happens
Large vesting events concentrate income. A 3,000-share vest in January has the potential to drag you into a higher bracket for the entire year — impacting the salary and bonus, as well as everything else. Run the numbers in Q4 — not Q2 of the following year.
2. Understand sell-to-cover
In order to prevent you from draining the checking account at vest, most brokerages automatically liquidate a slice of the shares to cover taxes at source. It hurts, but it’s safe. What it doesn’t fix is the withholding gap above — that math still falls on you.
3. Hold twelve months if the risk makes sense
Converting short-term gains to long-term ones saves real money on every dollar of appreciation. But holding concentrated stock in a single employer — especially your own — compounds your financial exposure. If the company stumbles, your income and your investments get hit at the same time. Selling some shares to diversify isn’t a concession. It’s the correct action.
4. Use tax-advantaged accounts to offset vest income
Maximizing the 401(k) or HSA contributions indeed lowers your adjusted gross income for the year. It won’t neutralize a large vest, but it reduces bracket damage — particularly useful in high-vest years.
Multistate and international situations
Relocate between states during a vesting period and each state may claim a portion of the income in accordance with where the work was performed — not where you live when the shares vest. International employees manage extra layers: treaty provisions and foreign tax credits, along with possible dual taxation. One misallocated vest has the potential to generate amended returns across multiple jurisdictions. This is not a situation to reconstruct after the fact.
Dimov Tax is ready to help you with RSUs
An RSU vest looks simple. Underneath, it’s a bracket calculation, a withholding gap, a holding period decision, and potentially a multistate allocation — all at once.Dimov Tax professionals run your numbers, close the withholding gap before April surprises, and establish a selling strategy around the actual tax data. Reach out to our experts today for 360 degree support.