How do you diversify when most of your wealth is in one stock?
The tax bill and the risk fight each other.

How risky is it to hold one stock?

Riskier than the stock's past return makes it feel. A diversified index carries only market risk. A single stock carries market risk plus company-specific risk that diversificationdiversificationSpreading investments across different assets so a drop in one doesn't devastate your entire portfolio.Full definition is supposed to erase for free. In a JPMorgan study of the Russell 3000 from 1980, roughly 40% of all stocks suffered a permanent 70%+ decline from their peak and never recovered, and the median stock underperformed the index over its lifetime. Two-thirds of stocks underperformed the index; the entire market's gain came from a small minority of winners verify×DON'T TRUST, VERIFYClaim: A single stock carries large, uncompensated company-specific risk; historically many individual stocks permanently lose most of their value while the index does not.Verify at: FINRA: Concentration Risk ↗FINRA's investor guidance explains why concentration adds risk without adding expected return. The 40%/70%/two-thirds figures come from J.P. Morgan Asset Management's "The Agony & the Ecstasy" study of the Russell 3000, cited in the body..

The trap is that a concentrated position usually feels safe precisely because it went up. It is up 5x, so it must be a great company, so it will keep winning. That is survivorship talking. The shares you own are the ones that already succeeded; nothing about a past run guarantees the next decade.

The hidden multiplier is correlation with your paycheck. If the stock is your employer's, and especially if new RSUs and options keep vestingvestingThe schedule by which you earn the right to keep employer contributions or stock grants. You usually need to stay at the company for a set period before the money is fully yours.Full definition into the same name, a bad year at the company can hit your salary, your bonus, your vesting equity, and your existing shares simultaneously. That is the exact scenario that wiped out Enron and Lehman employees, whose 401(k)s were stuffed with company stock. Treat your human capital as an undiversified holding in that same company, and the true concentration is worse than the brokerage screen shows.

What does it cost in taxes to just sell?

This is the whole reason people freeze. If you have held the shares more than one year, the gain is taxed at the long-term capital gains rate: 0%, 15%, or 20% federally as of the 2026 tax year, depending on your taxable income. On top of that, the 3.8% net investment income tax applies once modified AGI passes $200,000 single or $250,000 married filing jointly, so the top all-in federal rate is 23.8% verify×DON'T TRUST, VERIFYClaim: Long-term capital gains are taxed at 0/15/20% federally, plus a 3.8% net investment income tax above $200k single / $250k married, for a 23.8% top federal rate.Verify at: IRS Topic 409: Capital Gains and Losses ↗IRS Topic 409 lists the 0/15/20% brackets; the 3.8% NIIT is covered in the IRS instructions for Form 8960. Rates and income thresholds are indexed and change, so confirm for your filing year.. Short-term gains (held one year or less) are taxed as ordinary income, up to 37% federal, so waiting to cross the one-year mark matters.

Then add state tax. It ranges from 0% (Texas, Florida, Tennessee, and other no-income-tax states) to over 13% (California treats capital gains as ordinary income). A Californian in the top bracket can pay roughly 37% combined on a long-term gain; a Tennessee resident pays 23.8% or less.

Concrete: $500,000 of stock with a $50,000 basis is a $450,000 gain. At the 15% federal bracket with no state tax, selling it all in one year costs about $67,500. Push part of that gain into the 20% bracket plus 3.8% NIITNet Investment Income Tax (NIIT)A 3.8% extra federal tax on investment income for higher earners (above $200k single, $250k married).Full definition and the bill climbs fast, which is exactly why spreading the sale across tax years is the default move, not selling everything at once.

Brackets and income thresholds are indexed for inflationinflationA general increase in prices over time, meaning each dollar buys less than it did before.Full definition and change yearly; figures are the 2026 tax year. State tax is on top of everything shown.

What are the ways to unwind a concentrated position?

There is no single trick. There is a menu, and most people combine two or three. Ranked roughly from simplest to most specialized:

• Scheduled rule-based sell-down. Decide in advance to sell a fixed dollar amount or percentage every quarter until you hit your target weight, and just do it. Removes emotion and spreads the gain across tax years. If you are a corporate insider or ever hold material non-public information, this must be a written Rule 10b5-1 plan so your sales are legally protected (more below).
• Harvest gains in low-income years. A gap year, a sabbatical, early retirement before Social Security and RMDsRequired Minimum Distribution (RMD)The minimum amount the IRS requires you to withdraw annually from Traditional IRAs and 401ks starting at age 73 (rising to 75 in 2033). Calculated as account balance divided by your IRS life expectancy factor. Roth IRAs have no RMDs during the owner’s lifetime., or any year your taxable income dips into the 0% LTCG bracket is a window to sell shares at 0% federal tax. This is the single most tax-efficient tool most people never use.
• Donate appreciated shares. Give the most-appreciated lots to a donor-advised fund or charity instead of writing a cash check. You skip the capital-gains tax entirely and deduct fair market value (covered below).
• Exchange fund. Contribute your single stock into a partnership that pools many investors' concentrated positions; you get back a diversified interest and defer all gains for ~7 years. Accredited investors only, long lockup, and fees.
• Protective collar / hedgehedgeAn investment made to offset potential losses in another position, like buying gold to protect against currency declines.. Buy a put and sell a call to cap downside cheaply while you unwind, but stay clear of the constructive-sale rule (§1259).
• Direct indexing around it. Build the rest of your portfolio to deliberately underweight the sector and factor exposures your concentrated stock already gives you, and harvest losses elsewhere to offset the gains as you trim.
• NUA for employer stock in a 401(k). A specific IRS provision that can convert the gain on company stock inside your 401(k) into long-term capital gains instead of ordinary income (covered below).

Run your own numbers first: the portfolio X-ray tool shows your true single-name concentration once overlapping funds are counted, which is usually higher than people expect.

How does a scheduled sell-down (and a 10b5-1 plan) work?

The most reliable strategy is also the most boring: commit to a formula and follow it regardless of the price. For example, sell 5% of the remaining position every quarter, or a fixed $X, until the stock is under your 15% target. Spreading a $450,000 gain across, say, 4 tax years keeps more of it in the 15% bracket and out of the 20% + 3.8% zone, and it removes the "I'll wait for a better price" paralysis that keeps people 90% concentrated for a decade.

If you are an officer, director, or otherwise an insider, or you might ever have material non-public information, a discretionary sell-down invites insider-trading liability. The fix is a Rule 10b5-1 plan: a written trading plan adopted while you have no inside information, specifying the amount, price, and dates (or a formula) for future sales. Once it's in place, trades execute automatically and you get an affirmative defense against insider-trading claims. The SEC amended the rule in 2023 to add cooling-off periods (generally 90 days for insiders before the first trade) and other conditions verify×DON'T TRUST, VERIFYClaim: Rule 10b5-1 lets insiders adopt a written trading plan (while not aware of MNPI) that provides an affirmative defense to insider-trading liability; 2023 amendments added cooling-off periods.Verify at: U.S. Securities and Exchange Commission (SEC) ↗The SEC's rule text and its 2023 amendment release describe the affirmative defense and the cooling-off period requirements. Confirm current requirements before adopting a plan.. Even if you're not an insider, borrowing the 10b5-1 discipline (pre-commit, then automate) is the whole point.

Can you hedge the position without selling it?

Yes, but carefully. A protective collar buys a put option (a price floor) and sells a call option (a price ceiling) on the same stock. Structured so the call premium pays for the put, it can cap your downside for near-zero out-of-pocket cost while you unwind the position over years. The cost is your upside above the call strike.

The landmine is the constructive-sale rule, Internal Revenue Code §1259. If you hedge so tightly that you've effectively locked in your gain with no meaningful risk or reward left, the IRS treats it as if you sold the stock and taxes the gain immediately, even though you still own the shares. A collar with a wide enough band between the put and call strikes generally stays on the safe side; a near-zero-band collar, a short-against-the-box, or certain forward contracts can trip it verify×DON'T TRUST, VERIFYClaim: IRC §1259 (constructive sales) can force immediate gain recognition on an appreciated position if it is hedged to eliminate substantially all risk of loss and opportunity for gain.Verify at: Internal Revenue Service (IRS) ↗IRC §1259 and IRS guidance define constructive sales (short-against-the-box, offsetting notional principal contracts, certain forwards). Whether a specific collar triggers it is fact-dependent; get the strikes reviewed.. Treat a collar as a temporary bridge that buys time to sell, not a permanent way to dodge the tax.

What is an exchange fund, and is it worth it?

An exchange fund (not to be confused with an ETFExchange-Traded Fund (ETF)A basket of investments (stocks, bonds, or Bitcoin) that trades on a stock exchange like a single share.) is a private partnership where you and other investors each contribute a concentrated stock. In return you receive a proportional interest in the whole diversified pool, and because it's a like-kind partnership contribution rather than a sale, no capital gains are triggered. You've diversified without a tax bill today.

The catches are real. You must generally be an accredited investor (roughly $1M net worth excluding primary residence, or $200k+ income). There's a 7-year lockup required by the tax rules; leave early and you don't get the diversified basket. Fees run higher than an index fund, and the fund must hold at least 20% in illiquid assets (often real estate) to qualify, which drags returns. Critically, this is deferral, not forgiveness: your original low basis carries over to the fund interest, so the gain is still there when you eventually sell. It buys diversification and time, not a permanent tax escape. For most people, a disciplined multi-year sell-down at 15% beats locking money up for 7 years in a higher-fee vehicle.

How do gifting and NUA cut the tax?

Donate appreciated shares, not cash. If you're charitably inclined at all, this is the cleanest win available. Give shares you've held over one year to a donor-advised fund (Fidelity Charitable, Schwab Charitable, Vanguard Charitable are the large ones) or directly to a charity. You deduct the full fair market value (up to 30% of AGI for appreciated stock to a public charity or DAF) and you never pay capital-gains tax on the built-in gain. On $50,000 of stock with a $5,000 basis, you skip roughly $6,750–$10,700 of federal capital-gains tax and still get the full $50,000 deduction. A DAF lets you make one big gift in a high-income year, then grant it out to charities over time.

If you're over 70½, a qualified charitable distribution from an IRAIndividual Retirement Account (IRA)A personal retirement savings account with tax advantages. Two main types: Traditional (tax now, pay later) and Roth (pay now, tax-free forever).Full definition (up to $100k+, indexed) is a parallel move for retirement-account money, though QCDs are cash from the IRA, not appreciated shares.

NUA for employer stock in a 401(k). If your concentrated position is your own company's stock held inside a 401(k), the Net Unrealized Appreciation rules are a specialized, powerful tool. Done right, you pay ordinary income tax only on the stock's original cost basiscost basisWhat you originally paid for an asset. Used to calculate how much profit (or loss) you made when you sell.Full definition when you move it out, and the appreciation gets taxed at long-term capital-gains rates when you eventually sell, instead of ordinary income. That gap, ordinary rates up to 37% versus LTCG at 15–20%, can be large. NUA is technical and easy to blow with a wrong-order rollover; the full mechanics and the traps are on the NUA strategy page.

Your default should be sell-at-vest. RSUs are taxed as ordinary income the day they vest, so holding the shares afterward is an active decision to make a new concentrated bet on your employer with after-tax money, on top of the salary and future vesting you already have riding on that company. There's no tax reason to hold; the shares vested at fair value.

Set an automatic sell-to-cover-plus-diversify rule at every vest, and read tech worker finance for the full RSU/ESPP/option playbook.

What's a sane order of operations?

A workable default for most people, in order:

• Set the target weight (10–20% max) and calculate exactly how many dollars have to move.
• Route charitable dollars through the stock. Any giving you'd do anyway comes from the most-appreciated shares, not cash. Zero capital-gains tax, full deduction.
• Fill the 0% LTCG bracket every low-income year. Sell as much as fits under the 0% threshold for free.
• Sell the rest on a written schedule across multiple tax years to stay in the 15% bracket and out of the 20% + 3.8% zone. If you're an insider, wrap it in a 10b5-1 plan.
• Use NUA if it's employer stock in a 401(k), and consider a collar or exchange fund only if the position is genuinely too large to sell down inside a few years.
• Reinvest proceeds into a diversified allocation that deliberately underweights the sector your old stock lived in.

The mistake isn't paying the tax. The mistake is letting a fear of the tax bill keep 70% of your net worth riding on one company for another five years. A 15–24% one-time cost to remove a risk that has a roughly 1-in-3 chance of permanently gutting the position is, in expected-value terms, cheap insurance.

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