How Investment Fees Reduce Wealth

Why can a small annual fee mislead?

Kabir has seen fee comparisons before. They usually begin with a large investment, assume it earns a generous return for decades, and then show two very different ending amounts. The gap looks alarming, but the assumed return does much of the visual work. Change that return and both rupee amounts change, which makes it easy to dismiss the whole example as a forecast.

How much does a fee take from a lump sum?

There is a simpler way to see what the fee itself does. Imagine two identical investment pots. They start with the same amount on the same day, own the same investments and earn exactly the same return before fees. The only difference is that one pot has a charge and the other does not. This is not how two real funds will behave, but it is a useful thought experiment because nothing except the fee is allowed to change.

At the end of each year, the charged pot keeps whatever remains after that year's fee. The next year's fee is then taken from that smaller pot, and the process repeats. It is the same compounding that helps returns build on earlier returns, working in the opposite direction.

What share of the final amount does the fee take?

Suppose the fee-free pot's final value is cut into a hundred equal pieces. With a 2% annual charge over 30 years, the charged pot gives up 45.45% of that otherwise identical ending value. In round terms, only about fifty-five of the hundred pieces are left. The fee was small in any one year; repeating it made the final difference large.

This comparison does not need a forecast of the investment return. Whatever gross return one pot earns, the other earns too, so that shared part of the story falls out of the comparison. The return cancels because the two pots are deliberately identical before fees. It would not cancel if one fund earned more than the other or if money entered them on different dates.

The table applies the same thought experiment to several illustrative rates and holding periods.

At 1% a year, 26.0% of the matched ending amount is lost after 30 years. At 2%, the loss is 45.5%. Extend the same lump sum to 40 years and some rates in the table remove more than half of the amount the no-fee pot would have reached.

These are relative losses, not rupee forecasts and not claims about what any particular fund charges. The table answers one narrow question: when two otherwise identical lump sums differ only by a fixed annual fee, how much of the ending amount does that fee remove?

How much does a fee take from a monthly SIP?

Now imagine that Kabir does not invest one lump sum. Instead, he puts in one equal contribution at the beginning of every year for 30 years. The first contribution is present for the entire period and faces the fee 30 times. The final contribution arrives much later and faces it only once. Treating all of that money as though it had been invested on the first day would give the later contributions years of fees they never paid.

To show only this timing effect, set the gross return to 0%. With a 2% annual charge, the stream of equal beginning-of-year contributions loses 25.76% of its fee-free ending amount. The lump sum held for the entire period loses 45.45%. The fee itself has not become gentler; most of the contributed money has simply spent less time being charged.

A monthly SIP follows the same idea. Each instalment has its own starting date and must be followed from that date to the end. That is why one lump-sum percentage cannot describe every saving pattern.

How do you compare the fees of two funds?

In practice, the choice is rarely between a charged fund and a free one. It is more often between two funds with different charges. If the two imaginary pots again earn the same gross return, a 2% version finishes 42.1% below a 0.2% version after 30 years.

Real funds are not imaginary copies. Their portfolios, risks, services, tracking and gross returns can differ, so the lower-fee fund does not automatically finish ahead. Nor must the higher-cost fund outperform in every single year. What matters is where each fund finishes after its returns and fees have compounded over the complete period. The fee comparison shows the gap that higher gross performance would have to overcome; it cannot tell us in advance whether that performance will arrive. The limits of using an old record to answer that question are covered in why past performance is not enough to choose a fund.

Does a fee charged daily cost more?

Dividing the same stated fee into daily pieces produces a slightly smaller long-term loss in this example, not a larger one.

Take the same nominal 2% rate over 30 years. One full deduction at each year-end removes 45.45%. Dividing that rate into 365 equal daily deductions removes 45.12%. The daily version removes slightly less because every tiny deduction is taken from a balance that has already been made a little smaller by the previous one. For these two fixed-rate conventions, the annual deduction produces the larger loss.

That result should not be mistaken for an exact model of a fund's daily NAV. An actual scheme's expense ratio can change, and its published calculation follows regulatory and accounting rules. The example exists only to compare two precisely stated mathematical conventions.

What does a fee pay for?

A fee pays for services involved in running a fund and may also reflect distribution or advice. Mandate, risk, service, tracking, portfolio trading costs and tax all sit outside the two-pot comparison. A low charge does not make a fund suitable by itself, just as a higher charge does not prove that something valuable was delivered. The calculation isolates the cost; it does not rank funds or choose one for the reader.

The charge is also applied to the balance, not only to a gain. It therefore reduces the balance after a good period and after a bad one. Because the expense is reflected inside the scheme's value rather than appearing as a separate household payment, the annual percentage can be easier to notice than the much larger complete-period effect.

Portfolio trading costs do not fit the table's fixed-rate identity and can change with turnover and execution. Their mechanism is discussed, using Indian data, in factor investing, liquidity and turnover.

Sources and method

The figures are Bills & Brains calculations. The lump-sum comparison holds gross investment performance identical and changes only the fee. It calculates the share of the fee-free ending value removed using 1 − (1 − f)ⁿ, where f is the fixed annual fee and n is the number of years.

The contribution example applies the calculation separately to each beginning-of-year deposit, using its own holding period and assuming zero gross return. The daily comparison divides the nominal annual fee into 365 equal deductions per year.

These are mathematical illustrations, not historical fund returns or a reconstruction of any scheme's NAV. The fee rates are illustrative; they are not estimates of typical fund charges.

For real-world disclosure requirements, see SEBI's Master Circular for Mutual Funds, 20 March 2026, paragraph 11.2.2. It requires daily scheme-wise TER disclosure on AMC and AMFI websites, except for infrastructure debt fund schemes.

What to take away

The easiest way to understand fee drag is to compare two otherwise identical pots and let only the fee change. That shows how a modest annual deduction can remove a much larger share of a long-term ending amount. It also shows the boundary of the lesson: a lump sum and a stream of contributions do not have the same fee history, and two real funds do not have the same gross performance. The arithmetic makes one cost visible without pretending to settle the whole investment decision.