Investment Fee Calculator
What an annual fee costs over the life of an investment — usually far more than the percentage suggests.
A 1% annual fee does not cost you 1%.
How the investment fee calculator works
A 1% annual fee does not cost you 1%. It costs you 1% of a balance that would otherwise have compounded, every year, and the forgone growth on every pound taken compounds too.
Over thirty years at a 7% gross return, a 1% fee takes roughly a quarter of the final balance. Not a quarter of the return — a quarter of the whole thing. That is the single most under-appreciated number in personal investing, and it is why fee differences of a few tenths of a percent matter more than most fund selection.
The comparison row shows the same investment at a lower fee, because the decision is never "fee or no fee" — it is one fee against another.
Formula: net return = gross − fee; cost = FV(gross) − FV(gross − fee)
Worked examples
| Inputs | Total cost of the fee | Note |
|---|---|---|
| 100,000 plus 6,000 a year, 7% gross, 1% fee, 30 years | £279,291.99 | the fee costs a quarter of the balance |
| A cheap index fund instead | £61,539.53 | far less drag |
| A short horizon | £6,432.62 | the effect is much smaller |
FAQFrequently asked questions
How much do investment fees really cost?
Far more than the headline percentage. A 1% annual fee over 30 years typically removes around a quarter of the final balance, because the fee and its forgone growth both compound.
Why is the cost so much larger than the fee?
Because every pound taken in fees would otherwise have kept compounding for the rest of the term.
Does a 0.8% difference in fees matter?
Enormously over a long horizon — usually more than which fund you pick within the same asset class.
What fee is reasonable?
Broad index funds are widely available under 0.25%. Actively managed funds commonly charge 0.75% to 1.5% and must beat the index by that much just to draw level.
Does this include transaction costs?
No — only the annual management fee you enter. Trading costs, spreads and platform fees sit on top.
Where these figures come from
- CFA Institute — Quantitative Methods: The Time Value of Money — the discounting, annuity and IRR conventions used here
- US Federal Reserve — Regulation Z (Truth in Lending), APR calculation — why APR includes fees where a nominal rate does not
- MoneyHelper (UK Government-backed) — the UK's free money guidance service
Last checked: September 2026. These are the standard textbook formulas; the conventions named are those of the CFA Institute curriculum and ISO 80000 usage.