Picture two neighbours who each invest $100,000 on the same day, in funds that earn the same 7% a year before costs. Thirty years later, one has about $750,600 and the other has about $574,300. Nothing dramatic happened to either of them. The only difference was a yearly fee of 0.05% versus 1.00%, and that fee is called the expense ratio.
Think of an expense ratio as a toll booth on a road you were going to drive anyway. The toll looks tiny each time you pass, but you pass it every single year, and it is collected before you ever see your balance.
In this beginner guide to the expense ratio, you will learn what it is, why it matters more than most people expect, how to find and compare it in a few minutes, and which mistakes cost investors the most. By the end you will know what a good expense ratio looks like for the funds you own.
Real data from the Investment Company Institute: average fund expense ratios in 2025. Captured 1 October 2026.
What Is an Expense Ratio?
An expense ratio is the annual fee a fund charges to cover its running costs, shown as a percentage of the money you have invested in it. If a fund has an expense ratio of 0.40% and you hold $10,000, the fund takes about $40 a year. You never receive a bill. The cost is taken out of the fund's assets quietly, which lowers the fund's daily price a tiny amount.
The fee pays for things like the portfolio managers, research, record keeping, legal and audit costs, and customer service. Some funds also include a marketing charge known as a 12b-1 fee, which pays for distribution and sales support. All of it is bundled into the one number you see on the fund's fact sheet.
Two points are worth remembering early. First, the expense ratio applies to the whole balance, not just your profits, so you pay it even in a year when the fund falls. Second, it is quoted as an annual figure, which means it repeats every year you hold the fund and compounds against you in the same way that returns compound for you.
Funds tend to fall into two groups. An index fund simply copies a market index such as the S&P 500 or the MSCI World, so it needs very little human decision making and can charge very little. An actively managed fund pays professionals to pick investments in the hope of beating the market, and that team costs money. This is why index funds are usually the cheapest option on the shelf.
Why the Expense Ratio Matters
A fee of one percent sounds harmless. The trouble is that returns and fees both compound, but they pull in opposite directions. Every dollar paid in fees is a dollar that can no longer grow for the next 20 or 30 years.
$100,000 invested for 20 years at a 4% return grows to roughly $208,000 with a 0.25% fee, but only about $180,000 with a 1.00% fee, according to the US Securities and Exchange Commission's investor bulletin.
The same bulletin makes the point in plain words: fees may seem small, but over time they can have a major impact on your portfolio. Notice that the fee is certain while the return is not. You cannot control whether markets rise next year, but you can choose the cost of the funds you buy.
Costs also matter because they are one of the few things you can predict. Past performance does not reliably continue, yet a fund that charges 1.00% today will almost certainly charge close to that next year. When you cannot forecast the market, lowering the cost you pay is one of the most dependable ways to keep more of what you earn.
Here is how average costs look across the industry. The figures below are asset-weighted averages for 2025 reported by the Investment Company Institute, the trade body for US-registered funds.
Average expense ratios in 2025 (ICI)
| Index equity mutual funds | 0.05% |
|---|---|
| Index equity ETFs | 0.14% |
| Index bond ETFs | 0.09% |
| Money market funds | 0.24% |
| Bond mutual funds | 0.36% |
| All equity mutual funds | 0.40% (down from 1.04% in 1996) |
The trend is encouraging. Average equity mutual fund costs have dropped by 62% since 1996, and in 2025 some 92% of long-term mutual fund sales went to no-load funds, up from 46% in 2000. Cheap funds are now easy to find. The risk for most beginners is not a lack of options, it is simply never checking.
The SEC's own chart: the same $100,000 and the same 4% return, but three different annual fees. Captured 1 October 2026.
How to Check and Compare an Expense Ratio
You do not need a finance degree to find a fund's cost. The process takes a few minutes and works the same way for any fund, whichever country you invest from. Follow these steps for each fund you own or are thinking about buying.
Step 1: Find the Fund's Ticker or Full Name
Open your brokerage account or retirement plan and note the ticker symbol or exact name of each fund. Many people own several funds without realising it, because a single target-date or balanced product may hold other funds inside it.
Step 2: Look for the Expense Ratio on the Fact Sheet
Search for the fund's page on the provider's website and look for the line labelled expense ratio, ongoing charge, or total annual operating expenses. Different regions use different names for the same idea. If you see both a gross and a net figure, use the net number, because that is what you actually pay after any temporary fee waivers.
Step 3: Convert the Percentage Into Dollars
Multiply your balance by the expense ratio. A $25,000 holding in a fund charging 0.75% costs you $187.50 a year. Seeing the fee in money terms makes it much easier to judge whether the service is worth the price.
Step 4: Compare Against Similar Funds
Compare the fund with others that hold the same type of assets. A broad stock index fund should be compared with other broad stock index funds, not with a specialised sector fund. The free FINRA Fund Analyzer lets you search by ticker, name or keyword and compare the cost of owning funds side by side. If you prefer to see the wider picture first, our guides on ETFs for beginners and ETFs versus mutual funds explain where each type fits.
The FINRA Fund Analyzer, a free tool for comparing the cost of owning funds. Captured 1 October 2026.
Step 5: Decide Whether Extra Cost Buys Extra Value
A higher fee is only worth paying if it brings something you cannot get cheaper, such as a strategy you truly need or advice you will actually use. For plain exposure to a broad market, there is rarely a reason to pay more than the low end of the range. A useful rule of thumb many investors use is that broad index funds should cost well under 0.20%, while anything above 1.00% needs a very strong reason.
Your own comfort with ups and downs also shapes which funds suit you, so it helps to read about risk tolerance before you decide. Low cost is a tool, not a plan on its own.
Real Examples: What Fees Cost Over 30 Years
Let us make the toll booth visible. The table below assumes you invest $100,000 once and leave it for 30 years in funds that earn 7% a year before fees. The 7% figure is an illustrative assumption, not a forecast. The expense ratios used are the 2025 industry averages from the ICI report, plus a 1.00% fee that is common in higher-cost funds.
Ending value of $100,000 after 30 years (7% gross return)
| 0.05% (average index equity mutual fund) | about $750,600 |
|---|---|
| 0.14% (average index equity ETF) | about $731,900 |
| 0.40% (average equity mutual fund) | about $680,300 |
| 1.00% (higher-cost active fund) | about $574,300 |
$176,300 is the gap between the cheapest and the most expensive row, from a single number on a fact sheet. The investor who paid 1.00% handed over roughly a quarter of the potential end balance to fees.
Smaller amounts follow the same pattern. With $10,000 under the same assumptions, the 0.05% fund grows to about $75,100 and the 1.00% fund to about $57,400. The gap shrinks in dollars but not in proportion, which is why starting with cheap funds matters just as much for small accounts.
The second table shows what the fee costs you in plain money in year one, which is the number to check on your own statement.
Year-one fee on a $100,000 balance
| 0.05% | $50 a year |
|---|---|
| 0.14% | $140 a year |
| 0.40% | $400 a year |
| 1.00% | $1,000 a year |
A quick way to see how long the damage takes is the Rule of 72. Divide 72 by your return and you get the years needed to double your money. Fees lower your net return, so they stretch that doubling time, and the stretch grows with every year you stay invested.
Common Mistakes With the Expense Ratio
Mistake 1: Ignoring the Fee Because It Looks Small
A figure like 0.9% looks like less than one dollar in a hundred, so it is easy to wave away. The problem is repetition. It is charged every year on a balance that is, hopefully, growing. Always translate the percentage into a dollar amount and into a 20 or 30 year total before deciding it is small.
Mistake 2: Chasing Last Year's Winner
Investors often pick an expensive fund because its recent returns were high. Strong results can come from luck or from a style that happened to be in favour. The fee, by contrast, never takes a year off. Weigh performance against cost instead of looking at returns alone.
Mistake 3: Comparing Different Kinds of Funds
A bond fund at 0.36% and a broad stock index fund at 0.05% are not competing products, so putting them side by side tells you little. Compare each fund with its closest peers. A fair comparison is index fund against index fund, active fund against active fund.
Mistake 4: Forgetting the Other Costs
The expense ratio does not include everything. Brokerage commissions, trading spreads, account fees, advisory fees and taxes can sit on top. Check the whole bill, including any platform fee or adviser fee, because the total is what reduces your return. If you use an automated service, our robo-advisor guide shows how those layers of fees stack up.
Mistake 5: Never Checking Again
Fees change. Funds merge, providers cut prices, and cheaper rivals appear, which is part of why average costs have fallen so far since 1996. Set a yearly reminder to review each fund's expense ratio and swap an overpriced fund for a cheaper equivalent when it makes sense. Check any tax or trading cost of switching first.
Frequently Asked Questions
What is a good expense ratio?
For broad index funds and ETFs, anything near or below 0.20% is considered low, and many sit well under 0.10%. Actively managed funds usually charge more, with the industry average for equity mutual funds at 0.40% in 2025. The more a fund costs above those marks, the more it needs to justify the difference.
Is a 1% expense ratio too high?
For a plain index exposure, yes, because far cheaper alternatives exist. For a specialised or actively managed strategy, 1% is not unusual, but the SEC example above shows what it can cost: about $28,000 less than a 0.25% fund after 20 years on a $100,000 portfolio in that scenario.
Is the expense ratio charged every year?
Yes. It is an annual rate, deducted gradually from the fund's assets, so you pay it for as long as you hold the fund. You will not see a separate line item on your statement, which is why it is easy to overlook.
Do ETFs always have lower expense ratios than mutual funds?
Not always. The ICI report shows index equity mutual funds averaging 0.05% against 0.14% for index equity ETFs, so the label alone does not decide cost. Compare the specific funds you are considering. Our guide on using AI to compare ETFs can speed up the first pass.
Key Takeaways
- The expense ratio is the yearly percentage fee a fund takes from your balance, whether the fund goes up or down.
- Costs compound against you: about $208,000 versus $180,000 on a $100,000 portfolio over 20 years in the SEC example.
- Index funds are usually the cheapest, with 2025 averages of 0.05% for index equity mutual funds and 0.14% for index equity ETFs.
- Convert the percentage into dollars each year so the cost feels real.
- Compare funds only against similar funds, and use the net figure after fee waivers.
- Review your fund costs once a year, and remember that a toll that looks tiny still gets paid every time you pass.
This article is for education only and is not financial advice. Fees, tax rules and products differ between countries, so check the details for your own situation.