Every layer of cost: fee, spread, FX, platform, tax drag

A fund's ongoing charge is the yearly fee the fund takes from its own assets. It is the number on the label, but a user pays more than that. The all-in cost adds every layer between the user's money and the market:

• FX conversion when hryvnias become dollars and back;
• the bid-ask spread: you buy a little above and sell a little below the middle price;
• the fund's ongoing charge;
• a platform fee for the app or the broker account;
• tax drag: tax withheld on dividends before they reach you.

In our synthetic example a flat year costs $30 on $1,000, or 3.0%. Only $2 of it is the fund fee. When you compare two products, compare these totals, never one layer against one layer.

If you earn and spend in hryvnias and the fund is priced in dollars, your money changes currency twice: on the way in and on the way out. Each conversion costs the gap between the rate you get and the middle market rate, plus any explicit fee. It rarely appears on a fund's label, because it isn't the fund's cost; it belongs to the bank, broker or app that converts.

In our example each conversion is 1%, so $10 on the way in and $10 on the way out: $20 of the $30, two thirds of everything. The fund's own fee is $2, about 7%.

That changes where a product team should look first. Cutting the fund fee from 0.2% to 0.1% saves $1 a year on $1,000. Halving the conversion cost saves $10 on the round trip.

Sort every cost by when it is charged:

• one-off costs come with a trade: conversion on the way in, the spread when you buy, the spread when you sell, conversion on the way out. In the example: $22;
• yearly costs keep coming while you hold: the fund's ongoing charge, the platform fee and tax drag. In the example: $8 a year.

For a user who stays one year the one-off part dominates: $22 of $30. For a user who stays ten years the yearly part repeats ten times, about $75 or more, and the one-off $22 becomes a smaller share.

Two practical rules follow. To compare products for a long holder, turn one-off costs into a yearly figure by dividing them by the years held. And trading often makes one-off costs repeat, so they stop being one-off at all.

Compounding works on costs in the same way it works on returns. A yearly cost is a percentage of what is left that year, so the money shrinks by a factor every year, and the factors multiply.

In the example the three yearly layers together take about 0.8% a year: each year the balance is multiplied by 0.998 × 0.997 × 0.997 ≈ 0.992. Ten such years multiply it by about 0.923. Add the one-off layers at the start and the end and $1,000 becomes $902.63: $97.37, or 9.7%, gone without the market moving at all.

In a real market the return and the costs run side by side, so costs take a share of the growth, not only of the money you put in. That is why the next lesson stretches the same arithmetic to forty years.

A cost claim is honest when a user can compare it with another offer and reach the right conclusion. "Fees from 0.2%" fails that test: it quotes the smallest layer, and "from" hints that some users pay even less.

A better line has three parts. First, the yearly all-in cost: everything charged while the money stays invested, here about 0.8%. Second, the one-off costs of getting money in and out, here about 2.2% for the two conversions and the spreads. Third, a link to the full breakdown, layer by layer, with the assumptions (amount, currency, dividends).

It looks less exciting than one tiny number. But costs are the one part of investing a product can promise in advance, and users who later find a hidden layer stop trusting the rest of the screen too.

Two yearly layers are easy to forget because they don't sit inside the fund's own numbers.

The platform fee is what the app or broker charges for holding the account: a percentage of the balance, a fixed monthly amount, or both. A fixed fee hurts small balances most: $3 a month is 3.6% a year on $1,000 but 0.36% on $10,000.

Tax drag comes from dividends. When the companies in a fund pay dividends, a tax is often withheld before the money reaches the fund or you. In the example dividends are 2% a year and 15% of them is withheld, so 0.3% of the balance a year never gets invested. How much is withheld depends on where the fund is registered and on tax treaties; a later lesson reads that line on a factsheet.

Neither layer shows up in "fees from 0.2%", and together they are four times the fund fee here.