The quick answer
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Rebalancing brings a portfolio toward a chosen allocation; it is not a prediction of which asset will win next. Calculate drift first, then compare new contributions, distributions and sales with costs and tax visible.
An allocation can change without a new decision
Suppose a portfolio starts with a chosen mix of investments. If one part rises faster, its share of the total grows even when nothing is bought or sold. The portfolio can become different from the risk arrangement originally intended. Rebalancing is a process for reviewing that drift and deciding whether to move toward the chosen allocation.
The starting allocation still needs a reason. Copying a percentage from an online discussion does not make it suitable for the money's time horizon, access needs or the investor's capacity for loss. A rebalancing rule can help implement a plan, but it cannot rescue an unsuitable plan. Begin by writing what each asset is meant to do before setting a schedule to trade it back to a target.
Source: SEC Investor.gov: asset allocation, diversification and rebalancing
Calculate weights from current values
Imagine a fictional $100,000 portfolio with $60,000 in one asset group and $40,000 in another. The weights are 60% and 40%. Later, the first group is worth $72,000 while the second remains $40,000. The total is $112,000, and the first group's weight is about 64.29%, not 72%.
If the intended mix remains 60/40, the target values at that moment are $67,200 and $44,800. Moving $4,800 from the first to the second would restore the simple target before transaction costs and tax. The example explains arithmetic, not an appropriate allocation or a recommendation to sell. Use values from the same date and include the whole relevant portfolio rather than mixing one current price with another holding's older statement.
New contributions can change the required trade
Using the same fictional $72,000 and $40,000 holdings, suppose $8,000 of new money is available. Adding it entirely to the second group gives $72,000 and $48,000, exactly 60/40 of $120,000. No sale is needed in this particular example.
That result depends on the numbers and the existence of genuinely available new cash. It is not a universal reason to direct all future contributions to the weakest asset. If the portfolio is very large relative to new contributions, the effect may be small. Check whether the new investment remains appropriate and whether cash was already assigned to another obligation. Contributions, income distributions and withdrawals can all form part of the review, but each dollar should have only one job in the plan.
| Stage | First group | Second group | First group weight |
|---|---|---|---|
| Starting mix | $60,000 | $40,000 | 60% |
| After first group grows | $72,000 | $40,000 | 64.29% |
| After $8,000 new money to second group | $72,000 | $48,000 | 60% |
A percentage-point band is different from a percentage move
A rule might review an allocation when it moves five percentage points from a 60% target. That describes a 55% to 65% range. A rule using five per cent of the target would instead give a three-percentage-point move, because 5% of 60 is three. The phrases sound similar but create different trading triggers.
Write the rule numerically and include whether a threshold creates a review or an automatic trade. A calendar review, threshold review and combination approach have different administrative demands. This article does not claim one interval or band maximises returns. The purpose of a documented rule is to make the decision understandable before markets move, including how costs or unusual personal circumstances could justify waiting or seeking advice.
Selling creates a separate tax and record question
A sale can realise a capital gain or loss, depending on the asset, ownership and transaction history. The market value sold is not the gain itself. Acquisition parcels, expenses and adjustments matter, and Australian tax settings must be checked for the relevant year. Do not assume an allocation tool knows the cost base.
Before executing a rebalance, estimate the sale's tax implications using proper records and current guidance. Treasury has announced CGT changes from July 2027, so avoid extending an old discount assumption across every future trade. A lower tax bill is not the only objective, but an ignored tax bill can make the amount available for reinvestment smaller than the worksheet suggests. Record tax reserves separately from trading cash and ongoing spending.
Source: Treasury: announced tax-system changes from July 2027
Costs can outweigh a very small adjustment
Assume a fictional rebalance requires two trades with $10 brokerage each. The $20 transaction charge equals 2% of a $1,000 amount moved, before any spread or tax. Moving $20,000 with the same brokerage has a different proportional cost. This is a cost illustration, not a minimum size rule.
Check partial fills, platform fees and the effect of selling and repurchasing. A perfectly restored percentage can be expensive to maintain if the account is small and trading is frequent. Conversely, avoiding every cost indefinitely can leave a portfolio far from the intended exposure. Compare the actual size of the drift, the reason for the target and the all-in implementation costs. Precision to several decimal places is not itself evidence of a better investment decision.
Rebalancing does not guarantee better returns
An asset that has risen can continue rising after some is sold. An asset receiving new money can fall further. Rebalancing manages the relationship to a chosen allocation; it does not identify market tops and bottoms. Backtests can also depend heavily on dates, fees, tax treatment and the selected assets.
Keep risk management and return claims separate. MoneySmart's diversification guidance explains spreading exposure, while investment tracking helps identify changes in the portfolio. Neither creates a guaranteed profit from trading back to a percentage. Review whether the allocation still fits changed personal circumstances, but avoid rewriting the target solely because one investment recently performed well. A change in long-term plan should have its own explanation rather than being hidden inside a routine rebalance.
Sources: SEC Investor.gov: asset allocation, diversification and rebalancing · Moneysmart: track your investments
Make a short before-and-after record
Write the current total, actual weights, intended weights, proposed cash flows, estimated costs and unresolved tax questions. After any action, record the actual trades and resulting weights. Keep the reason for the decision and the next review date. This is enough to explain what changed without turning the process into a daily trading exercise.
Elaris's Freedom Clock does not rebalance investments or model asset-specific tax consequences. It can show the effect of a selected aggregate return or contribution assumption on a simplified timeline. Keep the real allocation process and its costs in separate records, and avoid entering a higher return merely because a portfolio has been rebalanced. A cleaner structure does not guarantee a higher growth rate or a safer work-optional date.
Check withdrawals as well as incoming money
A portfolio funding living costs can rebalance partly through which asset supplies a withdrawal. In the fictional $72,000 and $40,000 portfolio, taking a required $8,000 from the first group leaves $64,000 and $40,000. The new weight is about 61.54%, closer to 60% without making the allocation exact.
That does not mean the withdrawal is tax-free or that selling from that group is always appropriate. It simply shows why a planned cash need belongs in the arithmetic before separate buy-and-sell orders are created. Include transaction costs, tax reserves and the purpose of the remaining assets. A withdrawal strategy and a rebalancing review should communicate with each other rather than independently trading the same portfolio toward conflicting targets.
FAQ: Must rebalancing involve selling investments?
No. New contributions, distributions or planned withdrawals can sometimes move weights toward a target. Whether they are enough depends on portfolio size and the drift. Do the arithmetic first, then check suitability, costs and tax rather than assuming a sale is always required.
FAQ: Are five per cent and five percentage points the same?
No. Five percentage points around a 60% target gives 55% to 65%. Five per cent of that target is three percentage points. Write the intended rule explicitly so a vague phrase does not trigger more or less trading than planned.
FAQ: Does rebalancing guarantee buying low and selling high?
No. Prices can keep moving after a trade. Rebalancing restores an intended allocation under a chosen rule; it does not forecast turning points. Any claim of higher returns needs careful assumptions about the assets, period, fees and tax.
FAQ: Does the calculator account for tax when I rebalance?
No. Elaris does not reconstruct acquisition parcels or determine personal CGT. Keep a separate current-year tax assessment and transaction-cost estimate. The simplified retirement model should not be treated as an instruction to execute particular investment trades.
Put the next step into practice
Use your own confirmed figures and keep outstanding questions visible. Core tools are free, with no bank connection or compulsory account.
Open the Freedom Clock ↗Sources and editorial notes
Sources checked 25 October 2026. Worked examples are fictional illustrations. Rules, eligibility and product terms can change; use the official source for your circumstances.
- SEC Investor.gov: asset allocation, diversification and rebalancing ↗
- Moneysmart: track your investments ↗
- Treasury: announced tax-system changes from July 2027 ↗
General information, not an individual financial or legal assessment. AI-assisted drafting with source checks; independent professional review has not been completed. How we prepare our guides · Suggest a correction