Portfolio rebalancing restores the mix of assets you selected for your goals and risk capacity. It is a risk-control process: it reduces unintended allocation drift, but it does not guarantee higher returns or prevent losses.
The simplest useful policy states a target allocation, a review schedule, a tolerance for drift and the order in which trades will be made. Changing the target because your time horizon has changed is a separate decision from restoring an existing target.
In This Guide
- 1 Three practical methods
- 2 Worked example: a 60/40 portfolio
- 3 Before placing trades
- 4 Rebalancing is different from tactical trading
- 5 A policy you can fill in
- 6 Calculate the trade from current values
- 7 What if you are withdrawing money?
- 8 Check the accounts as one portfolio
- 9 Make a review record
- 10 Common question: should I rebalance after every market move?
- 11 Sources
Three practical methods
| Method | Trigger | Strength | Limitation |
|---|---|---|---|
| Calendar | A scheduled review, such as annually | Simple to maintain | Can miss large drift between reviews |
| Threshold | An allocation moves outside a stated band | Responds to meaningful changes | Requires monitoring; narrow bands can increase turnover |
| Cash flow | New deposits or planned withdrawals | Can reduce sales and associated tax costs | Small deposits may not correct a large imbalance |
A hybrid policy can review quarterly but trade only when a threshold is breached. The schedule tells you when to check; the band tells you whether action is warranted. Neither needs to follow financial news.
Worked example: a 60/40 portfolio
A hypothetical $100,000 portfolio starts with $60,000 in stocks and $40,000 in bonds. Stocks grow to $72,000 while bonds stay at $40,000. The total is $112,000 and stocks now represent 64.3%. Returning to a 60% target would require $67,200 in stocks and $44,800 in bonds, so a simple rebalance sells $4,800 of stocks and adds that amount to bonds.
A five-percentage-point band around the stock target would run from 55% to 65%. At 64.3%, this policy would not yet trigger a trade. A relative band uses different arithmetic: a 10% relative tolerance around 60% gives 54% to 66%. Write down which convention you mean.
If new contributions are available, direct them to the underweight asset first. Adding only bonds in this example would require $8,000 to restore a 60/40 mix without a stock sale: $72,000 ÷ $120,000 = 60%. Transaction costs and taxes are excluded from these examples.
Before placing trades
- Use total household exposure, including funds held in multiple accounts.
- Check whether funds overlap in their underlying holdings.
- Keep money for near-term spending outside a volatile allocation.
- Review spreads, commissions and any redemption restrictions.
- Consider realized gains, available losses and applicable tax rules.
It may be possible to make allocation adjustments inside retirement accounts without realizing taxable gains in a separate brokerage account. Account rules vary. Do not withdraw retirement money merely to rebalance; withdrawals introduce a different set of consequences.
Rebalancing is different from tactical trading
Momentum strategies, options hedges and constant-proportion portfolio insurance change exposures according to signals or models. They add assumptions, trading costs and potential failure modes. A “floor” in a model is not an insured capital guarantee, especially when markets gap or trading is constrained.
For a long-term investor, a written allocation policy is often more useful than trying to turn every market movement into a new strategy. Review risk tolerance and market volatility before selecting your bands.
A policy you can fill in
Record: target assets and percentages; review dates; allowable drift; cash reserves; which accounts to trade first; maximum acceptable costs; and the circumstances that justify changing the target. Use the same worksheet at each review. The rebalancing-frequency guide explains how to choose a monitoring cadence.
Calculate the trade from current values
For each asset group, target value = total portfolio value × target percentage. The difference between target value and current value shows the amount to add or remove before costs. Use the same valuation time for all holdings and check that targets add up to 100%.
In the 60/40 example, current stocks are $72,000 and the target is $112,000 × 60% = $67,200. The $4,800 excess is a sale in the simple trade-based method. Bonds have an equal $4,800 shortfall. Entering 60 as a spreadsheet multiplier instead of 60% would produce a result one hundred times too large.
What if you are withdrawing money?
Planned withdrawals change the total portfolio size. In the same example, taking $8,000 from stocks leaves $64,000 stocks and $40,000 bonds, or $104,000 overall. Stocks then represent approximately 61.54%. Selling from the overweight asset moved the mix closer to target, but did not exactly restore it.
To reach 60/40 after that $8,000 withdrawal, target values are $62,400 stocks and $41,600 bonds. One simplified sequence sells $9,600 of stocks, uses $8,000 for the withdrawal and buys $1,600 of bonds. These hypothetical calculations exclude costs and tax and do not prescribe an actual sale.
Check the accounts as one portfolio
Two accounts may individually look unbalanced while their combined holdings match the household target. Conversely, several “balanced” funds can overlap substantially. Group actual exposures, not just account names, before deciding what to trade.
In a combined household review, label ownership and access. Money in a partner’s account or a restricted retirement plan cannot always be moved as freely as cash in your own brokerage account. Improving an allocation on paper should not create an unsupported assumption about withdrawals or control.
The SEC’s rebalancing guidance identifies selling overweight assets, buying underweight assets and directing new contributions as possible approaches. Its warning to consider transaction costs and tax consequences remains relevant even when the arithmetic is straightforward.
Make a review record
| Field | Record at each review |
|---|---|
| Values and targets | Current amounts, percentages and valuation date |
| Trigger | Schedule and whether the defined band was breached |
| Proposed action | Contribution, withdrawal adjustment or trade |
| Costs and constraints | Fees, tax considerations and account restrictions |
| Result | Completed values and any remaining drift |
Use the wealth plan builder to connect the policy with the goal. Review the target itself after a genuine change in needs, rather than silently redefining it whenever one asset performs well.
Common question: should I rebalance after every market move?
A written schedule and tolerance band are meant to answer that question consistently. Very narrow bands can create repeated small trades and extra costs. Select the policy based on the allocation’s role and practical constraints, then monitor whether it remains workable.
Sources
- SEC Investor.gov: asset allocation and diversification
- SEC Investor.gov: diversification and rebalancing
Substantively reviewed October 9, 2026. Worked examples are hypothetical. Educational information; individual circumstances and jurisdiction matter.
