TLDR
If you receive RSUs, they are taxed as ordinary income when they vest, not when you sell. Most employers withhold at a flat rate that is often too low for high earners in California, which is why many HENRY professionals end up with unexpected five‑figure tax bills.
Why RSUs Feel Like a Bonus, but Behave Like a Tax Event
Restricted Stock Units rarely feel like income. They vest quietly, often sit untouched, and do not require an immediate decision. But for tax purposes, RSUs are treated exactly like salary.
When RSUs vest, the fair market value of the shares is added to your W‑2 income, even if you do not sell a single share. This dynamic is one of the most common sources of confusion for high earners.
Forbes has repeatedly highlighted that RSUs are particularly dangerous from a tax standpoint because taxes are triggered automatically, often before the employee understands the cash flow impact.
Forbes, Restricted Stock Units and Tax Planning Strategies
The RSU Withholding Trap Many High Earners Fall Into
Most companies withhold federal taxes on RSUs using the IRS supplemental wage rate. For many high earners, that rate is meaningfully lower than their actual marginal tax rate once federal, state, and surtaxes are considered.
California compounds this issue. RSUs can easily push total effective tax rates into ranges that standard withholding was never designed to cover.
The IRS itself treats RSUs as supplemental wages, and that classification is the root cause of the mismatch.
https://www.irs.gov/taxtopics/tc761
Three Numbers to Gather Before Your Next Vesting Date
You do not need complex models to improve clarity. Before your next vest, gather:
- The total dollar value of RSUs vesting this year
- Your year‑to‑date income excluding RSUs
- Total federal and state withholding year to date
This creates a fast reality check around whether withholding is aligned with your tax exposure.
A Simple “Gap Estimate” Framework
The purpose is not precision, it is awareness.
If your effective tax rate is materially higher than what has been withheld, the difference is the gap that often turns into a surprise balance due. Addressing it early creates flexibility around estimated payments, withholding adjustments, or timing decisions.
This is a planning issue, not an investment issue.
Second‑Order Effects HENRY Professionals Often Miss
RSUs do more than increase taxes. They can also:
- Trigger Net Investment Income Tax exposure
- Increase future Medicare premiums through IRMAA
- Phase out deductions and credits
- Create liquidity strain when shares are held but taxes are due
These impacts frequently show up one or two years later, which is why they catch people off guard.
How RSUs Fit Into a Coordinated Financial Plan
RSUs should not be evaluated in isolation. They interact with tax planning, investment diversification, risk management, and long‑term goals.
If you are curious how we help high earners coordinate these moving parts without defaulting to product‑driven advice, you can read more about our planning approach here:
How We Help
If you are still wondering whether you “have enough” complexity or assets to justify professional planning, this article may also be helpful:
Wealth Management Minimums, How Much Do You Need in San Diego?
Contact US
BAS Financial
5405 Morehouse Dr, Suite 245
San Diego, CA 92121
📞Phone:(909) 307‑4945
If you’d like to start with a conversation about your situation, goals, and whether working together makes sense, you’re welcome to reach out.