When Does a Loan Against Investments Make Sense?

Maya is offered money without selling anything

Maya has a substantial portfolio, some of it inherited and some of it a holding from her employer. She needs a sum of money for something specific, and rather than selling, she has been shown a facility: borrow against the portfolio, keep the investments, pay interest.

The appeal is obvious and partly real. She avoids a sale she did not want to make, she avoids realising a gain she would have to pay tax on, and the arrangement is quick. For a genuinely temporary need with a clear repayment source, this can be the right answer.

But the structure has a feature that the framing conceals. She has not converted an asset into cash; she has created two positions that move independently — a debt that grows at a contractual rate, and collateral whose value does whatever the market does. Whether that ends well depends on something she does not control.

Two balances, one of them uncertain

This is the whole of the analysis and everything else follows from it.

The loan side is certain. Interest accrues at the agreed rate, the amount owed rises predictably, and none of it is contingent on anything.

The collateral side is not. The portfolio's value moves, and the lender requires it to stay above some multiple of the loan. If it falls far enough, Maya faces a margin call: add more collateral, repay part of the loan, or have holdings sold to restore the ratio.

That last outcome is the one to understand properly, because it inverts everything the arrangement was for. She borrowed to avoid selling. If the market falls sharply, she may be sold out anyway — and at the worst possible prices, since the trigger is precisely that prices have fallen. The facility protects her from selling in every circumstance except the one where selling hurts most.

Nothing about this makes the instrument illegitimate. It makes it an instrument whose risk is concentrated in a specific, identifiable scenario, and the whole of prudent use is about surviving that scenario.

The comparison people make is the wrong one

There is a piece of reasoning that appears whenever this product is discussed, and it is worth dismantling because it sounds compelling.

The argument: the loan costs a certain rate, the portfolio is expected to earn more than that, so borrowing rather than selling leaves Maya ahead.

The problem is that the two numbers are not the same kind of thing. The loan rate is a contractual certainty. The portfolio return is an expectation with a wide distribution around it, and it can be negative for years — the measured spread is in the uncertainty of long-term equity returns. Comparing a certainty against an average and concluding the average wins ignores everything that matters, which is the shape of the distribution and what happens in its left tail.

And the left tail is not merely a poor outcome here; it is a compounding one. A large fall reduces the collateral, triggers the call, forces a sale near the bottom, and removes the assets that would have participated in the recovery. Maya ends up worse off than if she had sold a smaller amount calmly at the start.

Borrowing against investments does not remove the risk of selling. It converts a decision she controls into an event triggered by the market.

Where it genuinely fits

The narrow set of cases have four properties in common, and all four have to hold.

The need is temporary and well defined, with a known end. The repayment source is dependable and identified — a bonus, a maturing deposit, a sale already agreed, a receivable — rather than "the portfolio will have grown". The amount borrowed is small relative to the collateral, so that a severe fall still leaves ample margin. And the alternative genuinely is worse: a sale that would crystallise a large tax bill, or a holding that is operationally difficult to sell quickly.

The clearest legitimate case is bridging. Money is arriving on a known date, an expense falls due before it, and a short facility covers the gap. That is the same shape as an overdraft used properly, and it carries the same discipline: name the money that repays it before drawing.

Where it clearly does not

Three uses turn a bridge into a bet, and they are common enough to name.

Borrowing to invest more. This is leverage, and it should be called that. It amplifies both directions, and the downside path includes the forced sale described above, which means a bad outcome is worse than the same fall would have been unlevered.

Funding recurring expenses. If the shortfall repeats, there is no repayment source and the balance grows while the collateral is asked to support more each year. This is the overdraft failure mode with the added feature that a market fall can end it abruptly.

Postponing an unaffordable expense. If the expense cannot be afforded, borrowing against the portfolio does not change that; it defers the recognition and adds interest and a collateral risk in the meantime.

What to compare it against

Before taking the facility, the alternatives are worth pricing honestly, because the lowest rate is not automatically the lowest risk.

Selling part of the portfolio is the obvious one, and the objection to it is usually tax. That is a real cost and it should be calculated rather than assumed — a partial sale, chosen carefully across holdings, may cost considerably less than expected, and it carries no margin risk at all. Her concentrated employer holding is worth a particular look here: reducing it solves a concentration problem at the same time.

Using an emergency reserve, if the need is what a reserve is for. Reducing or delaying the expense. Or an unsecured facility, which will carry a higher rate and, crucially, no collateral call — paying more for the absence of that trigger can be entirely rational, and the comparison should be made explicitly rather than settled on the rate alone.

If she takes it

Three rules make the difference between a conservative bridge and a position that can fail.

Borrow well below the maximum offered, so that a severe fall in the collateral still leaves margin before any call. The lender's limit is set from the lender's risk tolerance, not hers.

Know the numbers in advance: what fall in the portfolio triggers a call, how much notice she gets, and what happens if she cannot meet it. These are answerable from the documents, and the time to answer them is before signing rather than during a market fall.

And keep the repayment plan real, with a date and a source. A facility with no repayment date has the same drift problem as an overdraft, with the additional feature that the market can end it for her.

What to take away

A loan against investments creates a certain debt against uncertain collateral, and the risk is concentrated in one scenario: a sharp fall that forces a sale at the worst prices, which is the outcome the arrangement was taken out to avoid.

Do not compare the loan rate against an expected return — one is contractual and the other is a distribution. Use it only where the need is temporary, the repayment source is named, the amount is small against the collateral, and the alternative is genuinely worse. Price the alternatives including an unsecured facility, whose higher rate buys the absence of a margin call. And if you take it, borrow well under the limit and find out in advance what fall triggers the call.