i What this calculator does
A portfolio drifts. What rises becomes a larger share of the total and what falls becomes a smaller one, so a plan set at 60/30/10 quietly becomes something else. Rebalancing sells what has grown and buys what has lagged, which is uncomfortable and is the point.
The research generally supports annual rebalancing or a threshold of about five percentage points of drift. More frequent rebalancing adds transaction costs and capital gains events without meaningfully reducing risk.
This calculator is for educational purposes only. Results are estimates and may vary depending on market conditions, spreads, commissions, platform settings, and exchange rates. It should not be considered financial advice.
How to use the Portfolio Rebalancing Calculator
Every field has a working default, so the calculator produces a result the moment the page loads. Replace the defaults with your own figures and the output updates when you press the button.
- 1. Local Equity Value (R)
- 2. Local Equity Target (%)
- 3. Offshore Equity Value (R)
- 4. Offshore Equity Target (%)
- 5. Bonds and Cash Value (R)
- 6. Bonds and Cash Target (%)
The result panel reports:
- Portfolio Value Across the three buckets
- Largest Drift Against the threshold of
Alongside the headline figures, the calculator reports local equity, offshore equity, bonds and cash, targets total. Those are the numbers that usually explain why the headline result came out where it did.
The breakdown below the result shows every step of the arithmetic, so you can check the figure rather than trust it. The formula panel names each input as it is used, which is useful if you want to reproduce the calculation in a spreadsheet.
Frequently asked questions
How often should I rebalance?
Annually, or when a holding drifts more than about five percentage points from its target. More frequent rebalancing adds brokerage and triggers capital gains without materially reducing risk. Less frequent lets the portfolio become something you did not choose.
Does rebalancing improve returns?
Not reliably. It controls risk, which is a different thing. Selling what has risen and buying what has fallen can add a little through the buy-low effect, but the honest case for it is that it keeps the portfolio matched to the risk you agreed to take.
What about capital gains tax?
Selling to rebalance in a taxable account triggers a disposal. Rebalancing with new contributions instead, by directing them to the underweight holding, avoids the event entirely and is usually the better route while you are still contributing.
Should I rebalance inside a tax-free savings account?
It is the easiest place to do it, because no capital gains arise. Note that a sale and repurchase inside a TFSA does not restore annual contribution room, so the trades themselves are free but the wrapper limits still apply.
Does Regulation 28 affect this?
Inside a retirement fund, yes: offshore exposure is capped at 45% and equities at 75%, so the targets must sit within those limits. A discretionary portfolio or a tax-free savings account has no such constraint.
What if my targets do not add to 100%?
The calculator says so rather than silently normalising them, because a target set that does not sum to 100% usually means something was mistyped rather than that a fourth bucket exists.
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