Should I Sell My RSUs When They Vest? Holding a Year Is Worth 4%.

A software engineer at a public company watches 3,000 shares land in a brokerage account on a Monday morning. The company already sold 864 of them to cover withholding. The remaining 2,136 are worth about $128,000, and they raise the question I get more than any other from people with equity: should I sell my RSUs when they vest, or hold them? Every coworker has an opinion and so does every advisor. For most people the answer is sell, and almost nobody gives the real reason.

When restricted stock units settle, the fair market value of the shares on the delivery date is ordinary wage income under IRC §83(a). It runs through payroll and lands in Box 1 of your Form W-2. Your basis in those shares is that same amount, under Treas. Reg. §1.83-4(b)(1). Sell them the same day and the capital gain is whatever the stock moved between the vest price and your execution price, which is usually a rounding error.

That part is true, and every page on the first screen of Google says it. What they leave out is what the vest did to your withholding. Employers treat an RSU vest as a supplemental wage payment and withhold at the optional flat rate, which IRS Publication 15 keeps at 22% for 2026. The mandatory 37% rate under IRC §3402(g)(1)(A) does not start until supplemental wages pass $1 million in a year, so nearly everyone gets 22% regardless of bracket.

A client couple once needed the real number on a bonus of roughly $225,000. I ran it at the marginal rate rather than the effective rate, layering federal, state, Medicare, and Social Security, which had already cut off because the wage base was met. An RSU vest is the same arithmetic. The 22% is a payroll convenience, not your rate, and the difference is cash you produce in April whether or not you still own the shares.

This is the argument that keeps people holding, and it deserves a number. Shares held more than one year get long-term capital gain treatment under IRC §1222(3), and the rate spread is real. The holding period starts the day after delivery, so the engineer above is a full twelve months out. Say the stock gains 20% over that year.

Twenty points of rate spread applied to a 20% gain works out to 4% of the position. That is the entire prize. To collect it you hold $128,160 of one company's stock, selected for you by your employer, for an extra year. A 4% drop in the share price over that year costs exactly what the tax saving is worth, and a single stock moves 4% in a quiet week. You are taking a coin flip to win a rounding error.

It gets worse if the stock falls hard, because the two sides are not taxed alike. The wage income was taxed at 35% and paid in cash. The loss comes back at $3,000 a year against ordinary income under IRC §1211(b), with the rest in carryforward. That math is in the RSU tax trap when the stock drops, and it is the most expensive thing I watch equity holders do to themselves.

Both are specific, and neither is a view on the stock. The first is a move. Wage income at vest is sourced to the state where you worked while the units were earned, which is why leaving California does not get you out of California tax on the vest itself. Appreciation after the vest is capital gain, and capital gain follows your residence on the day you sell. If you are relocating in a few months, that appreciation is the only piece of this still in play. California's ladder runs to 13.3% and Utah is flat at 4.45% for 2026, so at the top of the California range the spread is 8.85 points, or about $2,268 on the $25,632 gain above. California RSU tax after moving out of state covers the wage apportionment.

The second is charity. Shares held more than a year are long-term capital gain property, so giving them to a public charity or a donor-advised fund produces a deduction at full fair market value with no gain recognized. Give the same shares at eleven months and IRC §170(e)(1)(A) cuts the deduction back to your basis, which for RSU shares is the vest value you already paid tax on. If a tranche is earmarked for giving, that tranche waits, and note that for 2026 an itemizer's total charitable deduction is reduced by 0.5% of the contribution base under IRC §170(b)(1)(I).

What is not on the list is a belief that the stock is going up. The honest test is whether you would take the $128,160 in cash and go buy company stock with it. Almost nobody says yes. Holding is that same purchase, made by not deciding.

The most common error I see is not a bad hold decision. It is no decision at all. Sell-to-cover sells just enough shares to fund withholding, and people read the confirmation, see that shares were sold, and file the whole thing under handled. Four years of quarterly vests later they are 40% concentrated in one employer and cannot name the day they chose that.

The fix is a standing instruction instead of a quarterly judgment call. Most brokers will run an automatic market sale on the vest date. If you are a director or a Section 16 officer, that instruction belongs in a Rule 10b5-1 plan, which since the SEC's 2022 amendments carries a cooling-off period of at least 90 days for those insiders and 30 days for everyone else, so it has to be in place well before the vest you want it to cover.

Then deal with the shortfall. Selling the shares does not pay the tax by itself: add the gap to Step 4(c) of your Form W-4, or send a Form 1040-ES payment for the quarter the vest landed in. The IRC §6654 underpayment penalty is avoidable with the prior-year safe harbor, 110% of last year's tax when your prior-year adjusted gross income was over $150,000. The safe harbor calculator runs that, the RSU tax calculator runs the vest, and the long version is why you owe taxes on your RSUs.