How to Tell if Your Portfolio Needs Changing (and When to Leave It)

A job, a house, a child, a marriage, an inheritance, or a retirement date that moved. These change when you need the money and how much risk is appropriate, which is the input everything else depends on.

What to do. Re-derive the target allocation from the new horizon before touching any holding. The portfolio follows the plan; it does not lead it.

Markets move a portfolio away from whatever mix you chose. Left long enough it becomes a different portfolio, usually more concentrated in whatever ran hardest and right before that stops.

What to do. Rebalance back toward target, using new contributions first if you are still investing, because that avoids selling and therefore avoids realising gains in a taxable account.

The mechanics are in how to rebalance your portfolio.

Employer stock that vested, a winner that grew into a quarter of the portfolio, or several funds that turn out to hold the same companies. The exposure is real whether or not anyone chose it.

What to do. Reduce deliberately and over time rather than in one transaction, particularly where a sale realises a large gain. A schedule is easier to follow than a decision.

See how to check portfolio concentration, and how much of your portfolio in one sector.

A fund charging well above the index equivalent for substantially the same exposure, or a premium tier priced around tax features in an account where they cannot operate.

What to do. Swap the fund or drop the tier. This is the cheapest fix on the list and usually the fastest, especially inside a retirement account where selling has no tax consequence.

Overlapping funds mean two fees for one exposure and more concentration than the fund count suggests.

What to do. Keep the cheaper or broader one and consolidate, again minding the tax consequence in a taxable account.

If you sold during a decline, or wanted to badly enough that it occupied you, the allocation is more aggressive than you can actually hold. That is information about you, and it is more reliable than any questionnaire.

What to do. Move to a mix you would keep, accepting the lower expected return as the price of staying invested. A portfolio you hold beats a better one you abandon.

Each of these is a fact about the market or about your feelings, and neither is a fact about your portfolio. The tell is that none of them would change your answer if you did not know the recent returns: a portfolio that was correctly built last year is still correctly built after a bad quarter, and the only thing that has changed is how it feels to hold.

The one genuine exception is buried in the list. If a fall revealed that you cannot sit through it, that is real and it is the sixth signal in the first group. The distinction matters: you are not reacting to the fall, you are updating what you know about your own tolerance.

The ordering is by cost rather than by importance, which is counterintuitive and correct. Steps one and two are free, and most portfolios turn out to need only those. Step four is the only one that creates a tax bill, and doing it last means you arrive there having already fixed everything that could be fixed for nothing, often leaving much less to do.

In a large taxable account, step four is also worth spreading across tax years rather than completing in one. That is a sequencing judgement rather than a calculation, and it is one of the clearer places to get advice.

One habit prevents most of the avoidable damage, and it costs nothing. Before making any change, write a sentence saying what changed and which of the six signals it is. If the sentence is hard to write, or comes out as a claim about what markets will do, that is the answer: the change is a reaction rather than a decision.

It also creates something to check later. A note saying “reducing employer stock from 30% to 15% over four quarters because the concentration was not chosen” can be reviewed against what actually happened. A trade placed on a feeling leaves nothing behind, so the same feeling recurs and produces the same trade.

Five of the six signals are stable: an expensive fund stays expensive, overlap stays overlapping, and a horizon mismatch is as wrong next quarter as it is today. Waiting a month to think costs almost nothing on any of them.

Drift is the exception. It compounds, and it compounds in the direction that feels best, because the holding growing into an oversized share of the portfolio is by definition the one that has been doing well. Left alone through a strong run, a 60/40 portfolio can become something far more aggressive than anyone intended, and the correction becomes larger and more expensive the longer it waits, particularly in a taxable account where the accumulated gain is what you have to realise to fix it.

If you are going to act on exactly one thing from this page, act on that one.

Every signal in the first group is measurable, and running the numbers first stops a vague sense that something is wrong from turning into a trade. Performance against an index, look-through concentration, weighted cost, drift from target and fund overlap are the five, and they are covered in is my portfolio good enough.

An assistant connected to your own brokerage account can run those against your real holdings without taking custody of anything, which is how Walnut works. It does not tell you what to do with the answer, and it is not an investment adviser.