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Investment fee calculator UK

Investment Fee Drag Calculator: How Much Is Your Platform Charging You?

The Silent Killer of Compounding Returns

Investment fees may look small, but they can quietly take a large slice of your future wealth because money lost to fees no longer stays invested and compounding for you.

Beginner-friendly estimate with simple assumptions. Use the examples if you want a quick starting point.

Example presets

These examples show how even small fees can change outcomes over long periods.

Estimate the cost of annual fees

Enter a starting pot, regular contribution, expected return, and one combined annual fee.

Results in plain English

Pot with no fees

£237,964

A simple benchmark if the same return arrived with no annual charge.

Pot after fees

£205,336

Using a total annual fee of 1.00%.

Fees deducted directly

£19,018

The charge taken from the portfolio itself over the period.

Total fee drag

£32,629

This includes the lost growth on fees that were deducted earlier.

Takeaway

Small percentage fees can look harmless, but the drag compounds. Two portfolios with the same gross return can end very differently once costs are repeated year after year.

Example scenario

Example scenario

A small annual fee can make a bigger difference than many people expect over long periods.

  • Starting investment: £20,000
  • Monthly contribution: £300
  • Growth assumption: 7% a year
  • Time horizon: 25 years

This kind of example helps you see how a lower-fee setup can leave more money compounding for you instead of being lost to charges.

Learn the basics

How the Investment Fee Drag Calculator: How Much Is Your Platform Charging You? Works

Common Fees to Watch Out For

Platform Fees: These are the charges you pay to an investment platform to hold your money. In the UK they are often a small annual percentage, but even a modest-looking fee can meaningfully reduce long-term compounding.

Fund Charges (OCF or TER): Every fund has its own running cost. Low-cost tracker funds are often much cheaper than active funds, and that difference can add up over decades as more of your money stays invested.

Advisory Fees: If you use a financial adviser or managed service, there may be an extra annual charge on top of platform and fund costs. Ready to see how this affects your retirement? Try our Retirement Income Gap Calculator next.

Pros vs cons

Pros

  • Makes the impact of platform and fund charges much easier to see in pounds.
  • Helps explain why even a 1% fee difference can erode long-term wealth.
  • Useful for comparing low-cost trackers with more expensive investing setups.

Cons

  • Real portfolios can include multiple fees, taxes, and changing return patterns over time.
  • A lower fee is not the only factor when choosing a platform or fund.
  • This is a simplified comparison rather than a full provider recommendation tool.

Glossary

Platform fee
The annual cost charged by an investing platform for holding your account and assets.
Fee drag
The reduction in long-term investment growth caused by repeated fees taking money out of the portfolio.

Frequently asked questions

What is a good total fee?+

For many self-directed investors using index funds, keeping total annual costs below about 0.5% is often seen as strong value. Once total fees move above 1% to 1.5%, the drag can become much harder to ignore.

Does 1% really matter that much?+

Yes. A 1% fee does not just reduce one year of return. It also removes money that could have kept compounding for years, which is why the gap can become surprisingly large over time.

Are active funds worth the higher fee?+

Sometimes they can be, but many active funds struggle to beat low-cost market trackers after fees. That is why long-term investors often focus closely on costs.

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These calculators are for educational purposes only and do not constitute financial advice.

They use simplified assumptions and browser-based estimates. Read the full disclaimer before making important decisions.