Investing app fees explained: platform fees, subscriptions, fund costs and spreads

The most visible investing fee, commission per trade, has largely disappeared in the US and on several UK apps. What remains is less visible and mostly charged every year, which is why it matters more over time. This guide sets out each layer of cost, with examples from US and UK providers, and shows what the layers add up to over decades.

The layers of cost

Each is covered below.

Platform fees: flat or percentage

A platform fee pays for the account itself. It comes in two forms, and which is cheaper depends on the balance.

A flat fee costs the same whatever is held, so it is heavy on small balances:

Acorns charges a flat $4, $8 or $12 a month by plan. Betterment charges $5 a month below $24,000 and 0.25% a year from $24,000 or with $200 or more in monthly deposits. Wealthfront charges 0.25% a year for its automated portfolio.

Vanguard UK uses both forms: £4 a month below £32,000 and 0.15% a year above, capped at £375. The switch point is where the two are equal: £48 is 0.15% of £32,000. Hargreaves Lansdown charges up to 0.35% a year, which is £70 on £20,000. Freetrade has a free Basic plan and paid plans from £59.88 a year, with lower FX fees on the paid tiers.

Trading costs

Commission. Fidelity charges $0 for online US stock and ETF trades, plus $0.65 per options contract. In the UK, Hargreaves Lansdown charges up to £6.95 per online share deal, from £1.95 for funds, and nothing for purchases made through a monthly direct debit, which makes regular investing cheaper than one-off trades.

Stamp Duty Reserve Tax. In the UK, "When you buy shares, you usually pay a tax or duty of 0.5% on the transaction" (gov.uk). It applies to existing shares in UK companies. Units in OEICs and unit trusts bought from the fund manager are exempt, and foreign shares bought outside the UK normally are too.

Example. A £1,000 online purchase of a UK company's shares at Hargreaves Lansdown costs up to £6.95 in dealing charges plus £5 of SDRT: £11.95, or 1.2% before the shares have moved.

Currency conversion

Buying US shares from a UK account means converting pounds into dollars, and most apps charge a percentage for it. Freetrade's FX fee is 0.99% on Basic, 0.59% on Standard and 0.39% on Plus. On £1,500 of US shares that is £14.85, £8.85 or £5.85. The fee usually applies again when the shares are sold and the dollars converted back. Our guide to exchange-rate markups explains how to measure a conversion cost against the mid-market rate.

Fund running costs

Every fund charges a yearly running cost, taken from the fund's assets. In the US it is the expense ratio; in the UK, the ongoing charges figure. It never appears as a bill, because it is deducted inside the fund's price.

Vanguard UK lists fund costs from 0.06% to 0.79% a year. On £10,000, that is £6 or £79 a year, on top of the platform fee. A low platform fee on an app that offers only expensive funds can cost more than a higher platform fee with cheap funds.

Exit and transfer fees

Some costs appear only when leaving. Betterment charges $75 per outbound account transfer, Webull $75 per outgoing stock transfer, and Vanguard in the US $100 to close or fully transfer out. Vanguard US also charges a $25 annual account service fee, waived for customers who choose electronic documents.

How fees compound

Fees are taken every year from a balance that would otherwise keep growing, so the money they remove also stops earning. The table below assumes £10,000 invested once and an illustrative 5% return a year before fees. The return is an assumption chosen to show the effect, not a forecast; real returns vary and can be negative.

After 30 years, a 0.25% yearly fee has taken about 7% of what the balance would otherwise be, and a 1% fee about 26%. The gap between the two, about 8,100 on a 10,000 start, comes from a difference of 0.75 percentage points a year. That is why fees are the part of investing worth comparing closely: returns cannot be known in advance, but fees can.

Costs that do not show as a fee

• Spreads. Buying at one price and selling at a slightly lower one is a cost on every trade, larger on less frequently traded shares.
• Order routing. Some US brokers are paid for sending orders to particular trading firms. The broker's disclosures say whether it receives such payments.
• Cash. Uninvested cash in an investing account may earn less interest than a savings account, which is a cost of leaving money idle.

Tax wrappers

Tax wrappers change the tax, not the fees. In the UK, the ISA allowance is £20,000 for 2026 to 2027, and investments held in a stocks and shares ISA are tax-free. Platform, trading and fund fees still apply inside the ISA. In the US, retirement accounts such as IRAs have their own tax rules, and some apps add incentives: Acorns publishes a 1% IRA match in year one on Silver and 3% on Gold, and Robinhood Gold a 3% IRA match.

Working out your own cost

1. Note the balance you expect to hold, and how often you will add money or trade.
2. Add the platform fee at that balance, flat or percentage.
3. Add the running cost of the funds you would hold.
4. Add FX fees if buying overseas shares, and SDRT on UK shares.
5. Read the exit and transfer fees before opening the account.

Compare for your own balance

The investing fee calculator works out yearly fees for any balance and number of trades. Our US comparison and UK ISA comparison rank providers on published charges.