Investment Fee Drag Calculator

Investment fees compound dramatically. A 1% expense ratio on a 100,000 portfolio over 30 years at a 7% gross return produces roughly 187,000 in fee drag — the gap between compounding at 7% and at 6% once the fee is taken out. Compounding makes small fee differences enormous over time.

Run it with sensible defaults

Using an example portfolio of 100,000, an expense ratio of 1%, an annual return of 7%, and 30 years, the calculation works out to 186,876.39. These example values are a starting point, not a recommendation.

The levers in this calculation

The inputs — Portfolio Value, Expense Ratio %, Annual Return, and Years — do not pull with equal force. The rate and the time horizon usually dominate, because compounding means a small change in either reshapes the final figure more than a similar shift in portfolio size. Test this by doubling one input at a time.

How the math works

Compares portfolio growth with and without expense ratio. Difference = total fee drag.

Why investors run this

Running the numbers makes the trade-offs concrete. Small changes in the inputs can move the result more than intuition suggests, which is hard to judge without working it out.

What this doesn't capture

This is a simplified model that holds its assumptions constant. Real outcomes vary with market conditions, costs, taxes, and timing, so the figure is best read as one scenario rather than a forecast.

Worked example

Assume a portfolio value of 250,000 with an expense ratio of 0.5%, an annual return of 6%, and a 25-year horizon.

• Without fees, the portfolio compounds to approximately 1,072,968
• With the 0.5% fee, it compounds to approximately 953,348
• Fee drag over 25 years: approximately 119,620

Now change only the expense ratio to 1.5%:

• With the 1.5% fee, it compounds to approximately 751,359
• Fee drag: approximately 321,609

Trebling the expense ratio (0.5% to 1.5%) raises the fee drag roughly 2.7 times, from about 119,600 to about 321,600 — compounding at work.

When this metric matters

Fee drag becomes visible in several contexts:

• Comparing managed funds against index-tracking alternatives over multi-year periods
• Evaluating the lifetime cost of advisory fees on a growing portfolio
• Understanding the trade-off between active management and lower-cost passive holding
• Modelling retirement projections where fee assumptions differ significantly
• Assessing whether performance claims by fund managers exceed their fee burden

What the result shows and does not show

Shows: The nominal difference in portfolio value between two growth paths — one net of fees, one gross of them — and the cumulative fees extracted over the timeframe.

Does not show: Tax impact, inflation, actual sequence of returns, timing of contributions or withdrawals, fees that change over time, or whether the stated return is net or gross of all costs. Results are illustrations only, not forecasts or guarantees of future outcomes.