Portfolio Rebalancing Without Overthinking It: The Drift-Band Rule

• 1. Write down the target
• 2. Set a band, not a date
• 3. Use new money first
• 4. Mind where you rebalance
• 5. Check once or twice a year
• Free tools

A target mix (say 70% stocks, 30% bonds) drifts as markets move. Rebalancing brings it back. The two common mistakes are never doing it and doing it too often. A simple drift-band rule avoids both.

§1. Write down the target

List each fund and its target percentage. Keep it short: three or four funds is plenty for most long-term portfolios.

§2. Set a band, not a date

Rebalance only when a holding is more than about 5 percentage points away from its target (for example, stocks above 75% or below 65% on a 70% target). Small drifts don’t need action.

§3. Use new money first

Before selling anything, point new contributions at whatever is underweight. In many years that alone keeps the mix inside the band, with no trades at all.

§4. Mind where you rebalance

Inside tax-advantaged accounts (a 401(k), an IRA, an ISA and similar), selling usually doesn’t create a tax bill, so that’s the easiest place to trade. In a taxable account, selling winners can trigger capital gains tax, so new money and dividends are the gentler tools there.

§5. Check once or twice a year

Put a recurring reminder on the calendar. Look at the percentages, act only if something is outside the band, and close the spreadsheet.

§Free tools

• Portfolio rebalancing spreadsheet (free CSV for Excel / Google Sheets): https://smartbudgetsheets.surge.sh/templates/portfolio-rebalancing-spreadsheet/?utm_source=nostr
• 401(k) match calculator: https://smartbudgetsheets.surge.sh/calculators/401k-match-calculator/?utm_source=nostr

General information, not investment or tax advice. Rules differ by country and account type.