Tax-loss harvesting exchanges paper losses for realized losses that can offset gains—then replaces exposure with a disciplined substitute. Pair it with second-order effects (basis resets), boundary critique (which account owns the trade), and asset location so benefits land where law can recognize them.
1. Losses as Tax Inventory
Tax-loss harvesting is the disciplined sale of losers to realize capital losses, offset gains (and often a modest amount of ordinary income), then redeploy into a similar—but not identical—exposure so you stay invested. It is not "celebrating red screens"; it is recognizing that tax character is part of return.
Pair with second-order effects: harvesting resets basis lower, raising future gains if the asset rebounds. The second order is the tax timing swap, not free money.
"Harvesting without a map is trading one regret for another."
2. Wash-Sale Physics
The wash-sale rule punishes trivial round-trips: repurchasing the same or substantially identical security too soon can disallow the loss for current-year benefit. The boundary is legal and operational—document what you sold, what you bought, and why exposures remain appropriate. This is boundary critique with receipts.
3. Where Losses Live
Not all accounts swallow losses the same way. Asset location determines whether a realized loss is strategically useful or merely painful. Harvesting inside the wrong wrapper can be like catching rainwater with a sieve.
Spec ID where available; know short vs. long character.
Pre-commit substitutes that preserve risk exposure without tripping wash rules.
Quarterly discipline beats December panic; fewer errors, less narrative.
Compare estimated tax savings to trading costs and drift—if you cannot measure it, you are hobbying.
4. Behavioral Risk
Harvesting tempts market timing dressed as prudence. The system goal is tax alpha with stable exposure, not adrenaline. Balancing loops in your policy (rebalance bands) beat hero trades.
5. Entropy in Execution
Sloppy records turn tax alpha into entropy: amended returns, penalties, marital stress. Treat the harvest log like a ledger module—versioned, auditable, boring.
Build the lattice, not the legend.
Return to the Reading hub for essays, tools, and the rest of the 100-topic map.
OPEN READING HUB