All termsInvestments & Portfolio

Rebalancing

Trading a portfolio back toward its starting mix after market moves have shifted it.

Holdings that rise grow as a share of the whole, so a mix drifts without anything being bought or sold. A portfolio that starts at 60% stocks can end a strong decade for stocks nearer three quarters in them, carrying more risk than it started with.

Common approaches include rebalancing on a calendar, once or twice a year, and rebalancing only when a holding drifts past a set band, often around five percentage points. Directing new contributions toward whatever has fallen behind shifts the mix without selling anything.

The tradeoff is cost against drift. Selling in a taxable account can realize gains and a tax bill, while trades inside an IRA or 401(k) do not, and a portfolio that is never rebalanced ends up with whatever mix the market chose for it.

Worked through

A 60/40 mix left alone for ten years

Stocks returning 10% a year and bonds 3%, with nothing bought or sold.

Stocks at the start
$60,000
Bonds at the start
$40,000
Stocks after ten years
$155,625
Bonds after ten years
$53,757

The mix moved from 60/40 to about 74/26 without a single trade.

See your own rebalancing

Promi computes this from your linked accounts, with the definition one click from the number.

Open the live demo