Constructive sale tax trigger.

Constructive sale rules trigger when you hedge an appreciated position too aggressively (typically 80%+ of gains locked in via short sale, futures, or options). the tax authority treats this as a sale even though you still hold the position - immediate tax due. Designed to prevent indefinite tax deferral on gains.

500,000 position with 100,000 cost basis = 400,000 unrealized gain. Hedge locking in 90% of gain = 360,000 locked. Triggers constructive sale. At 20% LTCG rate: 72,000 immediate tax due. Position still held but tax already paid - eliminates tax benefit of holding.

To avoid constructive sale: keep upside exposure (less than 80% gain locked), use partial hedges (50-70% protection still allows full deferral), use longer-dated options out-of-the-money (less constructive sale risk). For substantial appreciated positions, consult tax advisor before hedging - getting it wrong creates immediate tax on positions you still hold.

Quick example

With position value of 500,000 and cost basis of 100,000 (plus hedge locks in of 90% and long-term capital gains rate of 20%), the result is 72,000.00. Change any figure and watch the output shift — it's often more useful to see the pattern than to memorise the formula.

Which inputs matter most

You enter Position Value, Cost Basis, Hedge Locks In %, and Long-Term Capital Gains Rate %. Not every input has equal weight. Flip one at a time toward extreme values to feel which ones move the needle most for your situation.

What's happening under the hood

Unrealized gain = position - basis. Locked gain = unrealized × hedge %. Tax = locked × LTCG rate. 80%+ hedge typically triggers. The formula is listed in full below. If the number looks off, you can retrace the calculation by hand — that's the point of showing the working.

Why investors run this

Most people's intuition for compounding is wrong — not because the math is hard, but because linear thinking doesn't account for curves. Running numbers through a calculator like this one is the cheapest way to recalibrate that intuition before making an irreversible decision about contribution rate, asset mix, or retirement age.

What this doesn't capture

Steady-rate math ignores real-world volatility. Actual returns are lumpy; sequence-of-returns risk matters most in drawdown; fees and taxes drag on compound growth; and behaviour changes in drawdowns can reduce outcomes below the projection. Treat the number as one scenario, not a forecast.