Micro-investing makes it possible to start investing with relatively small amounts, but a small starting balance does not make investment costs unimportant. In fact, when you are investing only a few pounds at a time, a fixed fee or recurring charge can take up a meaningful share of what you contribute.
This guide explains the main types of fees beginners should look for, how they can affect small portfolios, and how to compare the total cost of an investing app or platform without focusing on a single headline price.
Why Fees Matter More When You Invest Small Amounts
Every investment has costs somewhere in the process. Some are charged directly to your account, while others are built into an investment product or deducted from the value of a fund.
The important point is that fees reduce the amount of money available to remain invested and earn future returns. Investor.gov explains that even apparently small fees can have a substantial long-term effect on a portfolio. Its July 2025 investor bulletin illustrates this with a hypothetical $100,000 portfolio growing at 4% annually for 20 years: the ending value was approximately $208,000 with a 0.25% annual fee, compared with about $198,000 at 0.50% and $179,000 at 1.00%. These are illustrations, not forecasts, but they show why ongoing costs deserve attention. Investor.gov: How Fees and Expenses Affect Your Investment Portfolio
For a micro-investor, the same principle applies at a smaller scale. A £1 fee on a £25 contribution is 4% of that contribution before the investment itself has moved in value. Whether a particular fee is acceptable depends on the service provided and the full fee structure, but the percentage relationship is worth understanding.
The Main Types of Micro-Investing Fees
There is no single standard fee model for micro-investing platforms. A provider may use one charge, several charges, or a combination of account, transaction and investment-product costs.
1. Platform or Account Fees
Some investment services charge a recurring fee for maintaining an account or providing access to their platform. It may be a fixed monthly amount, an annual percentage of assets, or another structure.
For a larger portfolio, a fixed monthly charge may represent a relatively small percentage of the balance. For a very small portfolio, the same charge can be significant.
For example, if a hypothetical service charged £2 per month and you had £100 invested, the annual charge would equal £24, or 24% of the starting balance. That does not mean the fee is automatically unreasonable; it demonstrates why beginners should compare the charge with the amount they actually expect to keep invested.
2. Trading or Transaction Fees
A transaction fee is a charge associated with buying, selling or exchanging an investment. Depending on the provider, the fee may be fixed, percentage-based, or incorporated into another part of the pricing model.
Transaction costs can become particularly important for frequent small purchases. Before using an automated investing feature, check whether every scheduled purchase creates a separate charge.
Investor.gov describes transaction fees as costs that can reduce the overall amount of an investment portfolio and recommends checking what you will pay when buying, holding and selling an investment. Investor.gov: Understanding Fees
3. Fund or ETF Expenses
Buying a fund does not necessarily mean you only pay the platform. The fund itself may have operating expenses. One common measure is the expense ratio, which represents the percentage of a fund’s average net assets used each year for operating expenses.
These expenses are generally reflected in the fund’s value rather than appearing as a separate debit from your bank account. That can make them easy for beginners to overlook.
If your micro-investing platform lets you choose ETFs or funds, look beyond the platform fee and check the costs of the investment products themselves. Investor.gov notes that fund fees and expenses reduce investment returns and publishes guidance on comparing mutual fund and ETF costs. Investor.gov: Mutual Fund and ETF Fees and Expenses
4. Currency Conversion Fees
If a platform allows you to invest in assets denominated in another currency, currency conversion can introduce another cost. The charge may appear as an explicit conversion fee, a spread, or another exchange-related cost.
This matters if you are comparing an apparently low-cost platform that provides access to overseas investments with a platform that lets you invest in assets denominated in your own currency. Always check the actual conversion terms rather than assuming that a commission-free trade means the entire transaction is cost-free.
5. Deposit, Withdrawal or Transfer Charges
Some services may charge for particular account actions, such as certain withdrawals, transfers or other administrative services. Availability and pricing vary considerably between providers.
These costs may not matter if you rarely move money, but they should still be included in your comparison. A low trading fee does not necessarily mean a platform has the lowest total cost for your own pattern of use.
6. Inactivity, Minimum-Balance or Other Account Charges
Some investment services can have conditions attached to their pricing, such as minimum balances, account administration charges or other service-specific costs. Whether these apply depends on the provider and account type.
Read the current fee schedule and account terms before opening an account. Do not rely solely on an advert or a comparison article because pricing can change.
Fixed Fees vs Percentage Fees
One of the most useful ways to evaluate micro-investing costs is to convert a fee into a percentage of the amount you actually invest.
| Example fee | Investment amount | Fee as a share of amount |
|---|---|---|
| £1 | £25 | 4% |
| £1 | £100 | 1% |
| £1 | £500 | 0.2% |
| £5 | £100 | 5% |
This simple calculation does not tell you whether a platform is good or bad. It helps you understand how the same fixed charge can affect investors differently.
Percentage-based charges work differently. If a platform charges 0.5% annually on assets, the amount paid generally rises as the portfolio grows. A fixed charge can become proportionally smaller as the balance grows, while a percentage charge can continue increasing with the portfolio.
What Does “Commission-Free” Actually Mean?
“Commission-free” does not necessarily mean “cost-free.” A platform may remove a particular trading commission while other costs still apply.
Depending on the service, investors may still encounter platform charges, fund expenses, foreign-exchange costs, spreads, or other account-related charges.
The useful question is therefore not simply “Does this app charge commission?” Instead ask: What will I pay to buy, hold and sell the investments I actually plan to use?
This is especially important when comparing micro-investing apps. Our guide to micro-investing apps explains other factors to check, including investment choice, fractional shares, withdrawals and regulation.
How Fees Can Affect a £25 Monthly Investor
Consider a hypothetical investor who contributes £25 each month, or £300 per year.
If the platform costs £1 per month, the investor pays £12 per year. That is 4% of the £300 contributed during the year, before considering any investment performance.
Now imagine the same investor has built a £1,200 portfolio and the platform charges a hypothetical 0.5% annual platform fee. That would be about £6 for one year if the balance stayed at £1,200 throughout the period.
These examples are deliberately simple. Real portfolios change in value, fees can be calculated differently, and providers can combine several types of charges. The purpose is to show why beginners should translate fees into pounds and percentages rather than looking only at the advertised headline.
Fees Are Not the Only Cost
Cost comparison should include more than an account fee.
- Platform fee: What do you pay for using the service?
- Trading cost: Is there a charge when you buy or sell?
- Fund expense: What does the investment product itself cost?
- Currency conversion: Will exchanging currencies add a cost?
- Spread or execution cost: Could the price at which a transaction is executed differ from what you expected?
- Withdrawal or transfer cost: Are there charges for moving money or investments?
- Other account charges: Are there inactivity, minimum-balance or administrative fees?
The FCA has specifically reviewed how investment platforms communicate costs and charges to non-advised consumers. Its findings emphasise that consumers should be able to identify and understand investment charges when comparing platforms and products. FCA: Investment platform costs and charges review
How to Compare Two Micro-Investing Platforms
Suppose Platform A has a low-looking monthly fee but higher investment-product costs, while Platform B has no monthly fee but charges more elsewhere. You cannot make a meaningful comparison from the monthly fee alone.
Instead, create a simple comparison based on your expected behaviour:
- Estimate how much you expect to contribute each month.
- List every account or platform charge.
- Check the cost of buying and selling.
- Check the costs of the funds or ETFs you intend to hold.
- Check currency conversion terms if you need them.
- Check withdrawal and transfer conditions.
- Read the current fee schedule and key account documents.
- Calculate an approximate annual cost for your expected balance and activity.
This approach is more useful than choosing a platform because it advertises a single “zero commission” feature.
Should You Always Choose the Cheapest Platform?
Not necessarily. Cost is important, but it is only one part of the comparison.
A platform may provide features you value, such as a particular range of investments, recurring contributions, fractional shares, educational information or account functionality. Those features can have value, but you should understand what you are paying for them.
The goal is to understand the total cost and decide whether the service, investments and features fit your needs. Avoid assuming that the lowest advertised fee automatically means the lowest overall cost.
How Fees Fit Into Micro-Investing
Fees are one part of a wider micro-investing decision. Before focusing on costs, it helps to understand what micro-investing actually means and how the process works.
Start with what micro-investing is, then see our step-by-step guide to how micro-investing works. If you are considering fractional shares, our guide to fractional shares explains additional questions around ownership, dividends, voting rights and transferability.
You can also review our micro-investing guide for beginners for a broader checklist before getting started.
Micro-Investing Fees: Beginner Checklist
- Check the current platform or account fee.
- Check whether there is a transaction charge for each purchase or sale.
- Check fund or ETF expense ratios where applicable.
- Check foreign-exchange costs for overseas investments.
- Check withdrawal and transfer fees.
- Check minimum-balance or inactivity conditions.
- Check whether the fee is fixed, percentage-based, or both.
- Calculate the fee as a percentage of the amount you expect to invest.
- Read the provider’s current fee schedule before opening the account.
- Recheck fees periodically because pricing and product terms can change.
Frequently Asked Questions
Are micro-investing apps free?
Some platforms may advertise commission-free or low-cost investing, but “free” does not necessarily mean there are no costs. Check the complete fee schedule, including platform, investment-product, currency and transaction-related costs.
Can a small fee really matter when I only invest £25?
Yes. A fixed fee can represent a relatively large percentage of a small contribution. For example, a £1 charge on a £25 contribution is 4% of that contribution. The effect depends on the provider’s pricing and how often the fee is charged.
What is an expense ratio?
An expense ratio is a percentage of a fund’s average net assets used each year for operating expenses. Investor.gov explains that these costs can reduce the return investors receive from a fund.
Is a percentage fee better than a fixed fee?
Neither is automatically better. The impact depends on your balance, contribution pattern and how the fee is calculated. Convert both types of fee into an estimated annual cost for your own situation before comparing them.
Where can I find a platform’s fees?
Start with the provider’s current fee schedule, account terms and investment-product documents. Investor.gov also recommends reading disclosures and checking account statements so that you understand what you are being charged.
Final Thoughts
Micro-investing can lower the practical barrier to starting an investment habit, but small investments still need careful cost management. The most useful habit is to look beyond a platform’s headline commission and understand the total cost of buying, holding and selling the investments you plan to use.
For a beginner, the objective is not to find a magic “free” investment app. It is to understand the charges, compare them with your expected balance and activity, and make sure you know what you are paying for.
Educational note: This article is for general educational purposes and is not personal financial advice. Investment values can fall as well as rise, and fees, product availability and provider terms can change. Always check current information directly with the relevant provider and regulator before making an investment decision.
