How rebalancing creates tax churn (and how to avoid it)

Every global portfolio, at some point, needs to be adjusted.

An asset class does well, its weighting grows beyond what you intended, and the allocation drifts away from your original plan. The standard response is to sell the overweight position, buy the underweight one and this is what advisers call rebalancing.

What advisers talk about less is what rebalancing costs.

Every time you sell a position to rebalance, you trigger a taxable event. Under 24 months, you pay at your marginal rate (for most HNIs, 34% or higher). Over 24 months, 12.5%.

The market didn't punish you. You didn't make a bad call. The portfolio was doing exactly what it was supposed to do. But a portion of that gain leaves before it gets to compound further — simply because of how the adjustment was made.

This is tax churn. In this advisory piece, we unpack what causes it, when rebalancing actually makes sense, and what a more tax-aware approach looks like in practice.

Table of contents

• What is rebalancing?
• What is tax churn?
• When should I rebalance?
• How should I rebalance?
• The rebalance without selling
• Limitations of rebalancing

What is rebalancing?

Let’s say you have built a global portfolio with a certain allocation: 40% in commodities, 30% in emerging markets, and 30% in US equities. Commodities have a strong year. Your allocation drifts to 52% commodities, 26% emerging markets, 22% US equities. The portfolio is now heavily skewed toward a single thesis.

This is drift. Rebalancing brings it back to the original 40-30-30.

But why does it matter? When your portfolio drifts this far, you have become more exposed to commodities than you originally intended.

The portfolio is now more volatile, more sensitive to a reversal in that single thesis. If commodity prices correct and the dollar strengthens, the concentration hurts you harder than it should. Rebalancing restores the spread and keeps the portfolio honest about the level of risk you are actually running.

So the decision to rebalancing is almost always the right one. The question is what it costs to do it, and that is where most investors stop paying attention.

For a deeper read on how risk works inside a portfolio and why diversification matters, read: Take Risks but Don't Forget to Calculate Them

What is tax churn?

Every time you rebalance by selling a position, you trigger a taxable event. This is tax churn and for most investors, it is the largest invisible drag on a global portfolio.

Consider the commodity drift example from above. You started with $50,000 in a commodities position. After a strong run, it is now worth $65,000 — a $15,000 gain. You sell down to restore the allocation.

If that position was 18 months old, roughly $5,100 leaves the portfolio as tax. If it was 26 months old, roughly $1,875. The difference between those two numbers is nearly $3,200 — purely based on when the rebalance happened, not whether it was the right call. Either way, the capital that left as tax is no longer compounding inside the portfolio. On a $50,000 starting position, that is not a rounding error.

And this happens not once but repeatedly. Every rebalance that involves a sale is a potential tax event.

For investors, the alpha often lies in how and when the rebalancing happens. This is where good advisers differentiate themselves from the rest.

When should I rebalance?

There are three ways investors typically approach rebalancing.

Fixed period

This is the most common approach. The portfolio is reviewed and rebalanced on a fixed schedule, monthly, quarterly, or semi-annually, regardless of what markets have done.

It is simple and easy to follow. But it treats time as the trigger, not the portfolio.

A quarterly rebalance in a flat market still leads to trades. Positions get sold even when nothing meaningful has changed. The result is unnecessary churn and avoidable tax impact.

The calendar does not know what markets are doing.

Drift band

This approach ignores the calendar. A rebalance is triggered only when the portfolio has moved meaningfully away from its target allocation.

For example, if your commodities allocation moves from 40% to 48%, and your threshold is 5%, the portfolio flags a rebalance.

This is a cleaner approach. You act only when something has actually changed. Flat markets lead to no action, and unnecessary tax events are avoided.

But even here, the first question is not “what should we sell,” but “do we need to sell at all.”

If your next LRS remittance is due in the next few weeks, directing fresh capital into underweight positions can restore balance without triggering a single taxable event.

Conviction-based

Beyond drift bands, there is a third approach.

Here, rebalancing is not triggered by time or by thresholds, but by a change in the underlying investment thesis.

Capital is reallocated when something material shifts, when macro conditions change, when valuations diverge from fundamentals, or when the original reason for holding an asset is no longer valid.

This leads to fewer rebalances, and therefore fewer taxable events. More importantly, it ensures that decisions are driven by the investment case, not by mechanical rules.

For example, a position may breach the drift threshold after a strong run. But if the underlying thesis has strengthened, rebalancing simply because a number was crossed can be counterproductive.

In such cases, the right decision is often to do nothing, document the reasoning, and revisit it at the next review. A rebalance without a change in conviction is just a tax event dressed up as discipline.

How should I rebalance?

Once you have decided that a rebalance is warranted, the next question is how to execute it with the least possible tax damage. There are four ways to rebalance.

Sell here, buy there

The most common approach and the most expensive. You sell the overweight position and use the proceeds to buy the underweight one. If you are selling at a profit, that sale is a realisation event – taxable immediately. Avoid this unless you have exhausted every other option.

Draw money from bank

Use uninvested cash, either from a fresh LRS remittance you have not yet deployed, or cash sitting idle in your brokerage account. No sale, no realisation event, no tax. The existing positions stay untouched and their holding periods are preserved.

Use dividends

Direct dividend income into the underweight positions. The dividend is already taxable income at your slab rate, so you are not creating a new tax event, you are just redirecting existing income efficiently into where the portfolio needs it.

Tax Loss Harvesting (TLH)

The best option. Identify underperforming positions within the overweight asset class and sell those at a loss. The losses offset gains elsewhere in the portfolio, minimising the net tax impact, while the proceeds fund purchases in the underweight positions. The rebalance happens, the tax bill shrinks.

Suppose your equity allocation has drifted from 60% to 70%. Rather than selling your best performing equity positions, you identify the weakest performers within your equity holdings and sell those. The losses offset gains elsewhere, while the proceeds fund the bond purchases needed to restore the 60-40 balance.

At Paasa, this is the order in which we approach every rebalancing decision for our clients:

The rebalance without selling

The most tax-efficient rebalance is one where nothing gets sold. This sounds counterintuitive - rebalancing, by definition, means changing the allocation. But in many cases, the allocation can be restored without touching existing positions at all.

The approach works through addition rather than substitution. Instead of selling the overweight position and redirecting the proceeds, you direct your next LRS remittance entirely into the underweight positions. The overweight holding stays untouched. Its holding period continues to accumulate. And no realisation event is triggered.

This matters more than it might seem. Every month a position is held without being sold is a month closer to the 24-month threshold that separates a 34% tax bill from a 12.5% one. Preserving the holding period is not a minor administrative detail -- it is a meaningful financial outcome.

This approach works best when two conditions are met. First, the conviction behind the overweight position has not changed - if the thesis is intact, there is no investment reason to sell. Second, fresh capital is available or expected within a reasonable timeframe through LRS.

A portfolio built around a small number of non-overlapping instruments also helps here. Fewer positions means less frequent drift, which means the fresh capital approach can absorb more of the rebalancing work without requiring sales. This is one of the reasons Paasa's model portfolios are constructed the way they are.

Limitations of rebalancing

Rebalancing is not always the right answer.

There are situations where the mechanical application of any rebalancing approach - fixed period, drift band, or even conviction-based -- can work against you. A good adviser knows when not to rebalance just as much as when to.

Let your winners win

One of the most common mistakes is cutting strong performers too early.

A position may grow from 10% to 30% or even 40% of the portfolio. The instinct is to trim it back to the original allocation.

Sometimes that is the right call. But not always.

Many investors sold stocks like NVIDIA too early during its run, simply because it became “too large” in the portfolio. The position was reduced, the allocation looked cleaner, but the long-term upside was capped.

Not every position should be treated the same.

Broad, diversified exposures like index ETFs are often meant to be rebalanced regularly. But concentrated bets, high-conviction ideas, or asymmetric opportunities behave differently. These are the positions where outsized returns come from.

Rebalancing them too aggressively can reduce the very outcome the portfolio is trying to achieve. If you think you have a potential winner in your portfolio, evaluate fundamentals and market outlook before agreeing to an algorithmic rebalance.

When correlation breaks down

A diverse portfolio typically includes assets with varying degrees of correlation. Equities and bonds are usually uncorrelated, except during times of economic stress, like when inflation and real interest rates are both high. In these cases, they can move in sync.

In such cases, you might want to reconsider your entire portfolio composition rather than just rebalancing.

Transaction Costs

Every rebalance has a cost.

• Brokerage and transaction fees
• Bid-ask spreads
• And most importantly, taxes

Individually, these may seem small. Over time, they compound into a meaningful drag on returns.

A rebalance should only happen when the benefit of restoring the allocation clearly outweighs these costs. If the drift is marginal, or the portfolio risk has not materially changed, doing nothing is often the better decision.

A note on instruments

Everything covered so far is about rebalancing discipline; when to act, how to execute, and when to hold back. But there is a layer of tax drag that sits underneath all of this and is independent of any rebalancing decision you make.

Dividends.

Most US-listed ETFs (SPY, VOO, QQQ,..) are distributing by design. If you have built a global portfolio with US-listed instruments, dividend income hits your brokerage account quarterly as cash.

Under Indian tax rules, this is foreign dividend income, taxable at your slab rate in the year it is received. At 34% for most HNIs, a 1.2% dividend yield on a $100,000 portfolio costs roughly ₹1 lakh in tax every year, before a single rebalancing decision has been made.

Accumulating UCITS ETFs remove this drag structurally. When the underlying stocks generate income, it stays within the fund and is reinvested into the NAV. Nothing is paid out, nothing hits your brokerage account, and nothing is taxable that year. The income becomes part of the capital gain at exit, taxed at 12.5% after 24 months, not at your income tax slab every year it was earned.

The rebalancing discipline and the instrument choice are two separate problems with two separate solutions. Getting the rebalancing right while holding distributing instruments still leaves money on the table. Getting the instruments right while rebalancing carelessly still triggers unnecessary tax events. Both matter.

For a deeper read on how accumulating UCITS ETFs work for Indian investors, read: Accumulating UCITS ETFs vs US ETFs

About Paasa

Paasa is a platform that helps Indian investors invest in global markets including the US, UK, and China. You can trade directly through our platform, or work with our SEBI-registered advisory team who will build and manage a model portfolio for you, built around accumulating UCITS ETFs and managed with the rebalancing discipline covered in this piece.

If you want to see how this works for your specific allocation, book a call with our advisory team.