How to choose a stocks and shares ISA platform
Reviewed 5 June 2026. How to compare stocks and shares ISA platforms on cost, choice and protection, without naming any provider.
A stocks and shares ISA is a tax wrapper, not an investment in itself. The ISA shelters your growth and income from tax, up to the annual ISA allowance of £20,000 for 2026/27. The platform is the provider you open that ISA with, and where you choose and hold your investments. Picking the platform is a separate decision from picking the investments inside it, and it pays to treat them separately.
What to compare
Platforms differ in ways that add up over time. The points below are the ones that tend to matter most.
Cost. This is the big one, because fees compound against you for as long as you invest. Platforms usually charge either a percentage of the value you hold or a flat annual fee, and there can be separate charges for buying and selling funds or shares. As a rough rule, a percentage fee often works out cheaper on smaller pots, while a flat fee tends to win once a pot grows larger. The funds themselves also carry an ongoing charge, which is separate from the platform fee.
Investment range. Check that the platform offers the kind of investments you want, whether that is a simple range of low-cost index funds, a ready-made portfolio, or a wider choice of individual funds and shares. A beginner rarely needs the widest range; a confident investor might.
Ready-made or do it yourself. Some platforms offer ready-made portfolios matched to a risk level, which suit people who would rather not choose funds themselves. Others are built for picking your own. Neither is better; it depends on how hands-on you want to be.
Protection and regulation. Use a platform that is authorised by the Financial Conduct Authority, which you can confirm on the FCA Register. Authorised firms are covered by the Financial Services Compensation Scheme, which can protect up to £85,000 if the firm itself fails. That protection does not cover investment losses, only the failure of the provider.
Usability and service. A clear app or website, sensible tools and reachable customer service matter more than they sound, because an account you find easy to use is one you are more likely to keep on top of.
Moving an existing ISA
If you already hold an ISA elsewhere, you can usually transfer it to a new platform without losing its tax status. The key is to use the provider's ISA transfer process rather than withdrawing the money yourself, which would lose the ISA wrapper. Check for any exit fees before you move.
Where this fits
If you are still deciding whether an ISA is the right wrapper at all, our ISA vs Pension Calculator compares the two for your situation, and our guide on starting investing covers the wider first steps. To see how regular contributions grow inside a wrapper, use the Investment Calculator.
Sources and useful reading
- GOV.UK: Individual Savings Accounts
- FCA Register: check a firm is authorised
- FSCS: investment protection limits
Common questions
A few questions that come up on this topic.
What is the difference between an ISA and a platform?
The ISA is the tax-free wrapper, set by HMRC rules, with a £20,000 annual allowance for 2026/27. The platform is the company you open the ISA with and hold your investments through. You choose the platform, then the investments inside it.
Are flat-fee or percentage-fee platforms cheaper?
It depends on how much you hold. A percentage fee is often cheaper on smaller pots, while a flat annual fee tends to be cheaper once a pot grows large. Compare both against the amount you expect to invest.
Is my money safe on an investment platform?
If the platform is authorised by the FCA, your money is covered by the Financial Services Compensation Scheme up to £85,000 should the firm fail. That does not protect you from investment losses, which are a normal part of investing.
Can I move my ISA to a different platform?
Yes. Use the new provider's ISA transfer process so the money keeps its tax-free status. Withdrawing it yourself would lose the ISA wrapper, so always transfer rather than cash out.
This guide is general information for UK readers, not financial advice or a personal recommendation. It does not name or endorse any specific provider. The right choice depends on your own circumstances.
Investing involves risk. The value of investments and any income from them can go down as well as up, and you may get back less than you put in. Tax and pension rules can change.