Stocks and shares ISA for beginners: how to compare platforms

By the Grow & Guard editorial team · Last updated · 8 min read

A stocks and shares ISA lets you invest without paying tax on the returns. This guide explains how they work and what to compare when choosing a platform. It does not recommend any platform or investment.

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General information only, not financial advice. Grow & Guard is not authorised by the Financial Conduct Authority to give advice. It is not a personal recommendation. Check details with the provider and consider independent advice before making financial decisions.

Capital at risk. Investments can fall as well as rise and you may get back less than you put in. Past performance is not a reliable guide to future returns. If you are unsure whether investing is right for you, consider free guidance from MoneyHelper or regulated financial advice.

What is a stocks and shares ISA

An Individual Savings Account (ISA) is a tax wrapper. Inside a stocks and shares ISA you can hold investments such as funds, shares and bonds, and according to GOV.UK you do not pay tax on income or capital gains from investments held in it. You do not need to declare ISA income on a tax return.

In the 2026 to 2027 tax year you can put up to £20,000 in total into ISAs. You can split that allowance across the four types: cash ISAs, stocks and shares ISAs, innovative finance ISAs and Lifetime ISAs. You must be 18 or over to open a stocks and shares ISA.

Before you invest: three checks

  1. Emergency savings first. Most guidance suggests keeping a cash buffer for emergencies before investing, so you are not forced to sell at a bad time.
  2. Time horizon. Investing is generally for money you will not need for at least five years.
  3. Debts. Paying off expensive debt, such as credit cards, usually comes before investing.

The fees to compare

FeeWhat it isWhy it matters
Platform or account feeA percentage of your pot each year, or a flat monthly or annual feeFlat fees tend to suit larger pots; percentage fees can suit small pots
Dealing or trading chargesA fee each time you buy or sell, which may be zero on some platformsMatters if you invest monthly or trade often
Fund chargesThe ongoing charge of any fund you hold, set by the fund managerPaid on top of platform fees; index funds are often cheaper
Foreign exchange feesA charge for converting pounds to buy overseas sharesCan add up if you buy US or European shares
Transfer and exit feesCharges for moving your ISA elsewhereWorth checking before you open an account

A simple way to compare is to work out the total yearly cost in pounds for your expected pot size and investing habit, rather than comparing headline percentages.

Ready-made or do it yourself

  • Ready-made portfolios: you choose a risk level and the provider picks and rebalances the investments. Simpler, but usually with a management charge.
  • DIY platforms: you choose your own funds or shares. More control and potentially lower costs, but you make the decisions.

How to check a platform is regulated

Only use an investment platform authorised by the Financial Conduct Authority (FCA). Search for the firm on the FCA Financial Services Register and check that its name, address and website match the one you are using. Scammers clone real firms' details.

If an authorised investment firm fails, the FSCS may be able to compensate eligible investors up to £85,000 per person per firm. That does not cover investments falling in value. Use the FSCS checker to see how a provider is covered.

Moving an existing ISA

If you already have an ISA, always use the new provider's transfer service rather than withdrawing the money yourself, or you may lose the tax benefits. Transferring does not use up your allowance for the year.

Why this page has no "best ISA" list

Recommending specific investment platforms is regulated activity in the UK, and the right platform depends on your circumstances. We explain how to compare instead. Business owners can also look at pensions, which have their own tax advantages; MoneyHelper explains the basics for the self-employed.

Sources we checked

All checked on 1 November 2026. Prices and features change, so confirm on the provider's site before you buy.

Frequently asked questions

How much can I put in a stocks and shares ISA?
In the 2026 to 2027 tax year you can save up to £20,000 in total across all your ISAs, according to GOV.UK. You can put all of it in a stocks and shares ISA or split it between ISA types.
Do I pay tax on a stocks and shares ISA?
GOV.UK says you do not pay tax on income or capital gains from investments in an ISA.
Can I lose money in a stocks and shares ISA?
Yes. The ISA wrapper protects you from tax, not from losses. Investments can fall in value and you may get back less than you put in.