Double-Trigger RSUs: The Pre-IPO Tax Guide

A restricted stock unit is a promise: satisfy the conditions and the company delivers shares. With standard single-trigger RSUs, the only condition is time, and shares are delivered (and taxed) as the schedule vests. A double-trigger RSU adds a second condition that must also be met before any shares move: a liquidity event, defined in the plan, usually an IPO, a direct listing, or an acquisition, and in some plans a company-sponsored tender offer.

The design exists to solve a tax problem, not to be clever. Because RSU income is taxed when shares are delivered, a private company that delivered shares on ordinary time-vesting would hand employees tax bills on stock they cannot legally sell. Gating delivery on liquidity means the tax arrives at the same moment a market for the shares does. That is genuinely employee-friendly. The cost is concentration: everything arrives at once.

Two structural details matter more than most people realize. First, the units are deferred compensation, so the settlement schedule is built around Section 409A, the rules that restrict when deferred pay can be delivered and punish violations with a 20% additional tax. That is why your company cannot simply release shares early or let you pick a settlement date. Second, most double-trigger grants expire, commonly around seven years from grant. Fully vested units can be forfeited if no liquidity event happens in time, a term worth locating in your grant agreement today rather than in year six.

Public companies almost always issue single-trigger RSUs, because their stock is already liquid. Private companies moved overwhelmingly to double-trigger after early single-trigger experiments left employees with phantom tax bills. If you have RSUs, which kind you hold determines your entire tax calendar:

The compressed income pattern in the right-hand column is the story of this whole page. A single-trigger employee earning $150,000 of RSU income a year for four years pays tax in four manageable annual layers. A double-trigger employee with the identical grant can recognize $600,000 of income in one year, which changes brackets, phase-outs, Additional Medicare Tax, and the adequacy of withholding all at once. For the vest-by-vest mechanics that public-company employees deal with, see our guide to RSU tax withholding.

When the liquidity event finally fires, the plan settles every unit that has already time-vested. Depending on the plan, that happens on the IPO date itself, on a scheduled settlement date shortly after, or occasionally in installments timed around the lockup. Whenever delivery happens, the tax math is the same:

Ordinary income equals shares delivered times the market value on the settlement date. It is W-2 wage income, subject to federal and state income tax, Social Security tax up to the wage base ($184,500 in 2026), Medicare tax, and the 0.9% Additional Medicare Tax on wages above $200,000.

Withholding happens through share withholding or sell-to-cover. Most companies withhold shares equal to the required tax deposit and deliver the net. Federal income tax withholding uses the flat supplemental rate: 22% until your supplemental wages for the year exceed $1 million, 37% on the excess.

Your basis is set at the settlement-date value. Whatever happens to the stock afterward is capital gain or loss against that basis, long-term once you have held the delivered shares more than a year. The ordinary-income layer never gets recomputed, which is the root of the lockup trap in section 5.

Units that have not yet time-vested at the liquidity event simply continue vesting on schedule, and because trigger two is now permanently satisfied, they settle and are taxed at each remaining vest date like ordinary public-company RSUs.

Want to run your own numbers? Our free RSU tax calculator estimates the income, the flat withholding, your real marginal tax, and the gap for any settlement or vest amount.

1. The flat 22% is a withholding rate, not your tax rate.

The settlement is supplemental wages, withheld at 22% below $1 million of cumulative supplemental pay. Anyone whose settlement is large enough to matter is usually in the 32%, 35%, or 37% bracket, so the withholding runs 10 to 15 points light on every dollar. Ironically, the very largest settlements are safer: above $1 million the mandatory rate becomes 37%, which usually overshoots. It is the $200,000-to-$900,000 settlements that produce the nastiest April surprises.

2. The lockup mismatch can turn a paper gain into a real tax debt.

Your income is fixed at the settlement-date price, but a standard lockup keeps you from selling for roughly 90 to 180 days. If the stock falls during that window, the tax does not fall with it. Settle at $45, watch the stock trade at $20 at lockup expiration, and you owe tax on $45 while holding $20 shares; selling then produces a capital loss that offsets other gains but only $3,000 per year of ordinary income. Post-IPO stocks are volatile in exactly this window, and the people who got hurt worst in past IPO cycles were the ones who did not sell anything at lockup expiration because the price had dropped and they were anchoring on IPO day.

3. Underpayment penalties compound the gap.

A five-figure shortfall paid the following April can also trigger an underpayment penalty computed quarterly. The safe harbors are your friend: pay in 90% of the current year's tax, or 100% of last year's (110% if last year's AGI exceeded $150,000), through withholding or timely estimates, and the penalty disappears no matter how large the April balance is. In an IPO year, hitting the prior-year safe harbor is usually the cheapest, most certain move, because last year's tax was computed before the windfall.

1. Model the settlement while the company is still private.

You already know your time-vested unit count and can estimate a settlement price range from the last 409A valuation or recent tender pricing. Multiply, apply your real marginal rate, subtract 22%, and you have the gap. Knowing it is $46,000 a year early converts a crisis into a savings plan of a few thousand dollars a month.

2. Pre-commit to a post-lockup selling plan.

Decide in advance what fraction you will sell at lockup expiration regardless of price, at minimum enough to cover the tax gap. A written plan made before the IPO beats a judgment call made while watching a ticker. Concentration that felt tolerable at a private company valuation feels very different when it reprices daily.

3. Sweep the adjacent tax moves in the settlement year.

A one-time income spike is also a one-time planning window: charitable bunching or a donor-advised fund contribution lands at your highest-ever marginal rate, and the settlement year is usually the wrong year for other elective income like Roth conversions. If some of your equity is options rather than RSUs, exercise sequencing interacts with all of this; see the comparison in RSUs vs stock options and the AMT math in ISO AMT.

4. Get the W-2 and 1099-B to agree at filing time.

After settlement, your broker's 1099-B will typically show a basis that omits the W-2 income, overstating your gain if copied blindly; the fix is a Form 8949 basis adjustment. It is the same trap that catches ESPP sellers, and IPO-year returns are where it does the most damage.