UK Investment Platform Comparison – ISAs

£20,000 annual allowance

You can put up to £20,000 into ISAs each tax year – and this resets every April. There’s no limit on how much you can build up over time, just how much you can add each year. The allowance is shared across all ISA types, so if you put £5,000 into a Cash ISA, you’ve got £15,000 left for a Stocks & Shares ISA.

From April 2027, the Cash ISA allowance drops to £12,000 for under-65s – but the Stocks & Shares ISA allowance stays at £20,000. Source: HMRC

Tax year deadline

The tax year runs from 6th April to 5th April. Any unused allowance doesn’t roll over – if you don’t use it, you lose it. There’s usually a rush in late March.

Multiple providers allowed

Since April 2024, you can pay into multiple Stocks & Shares ISAs in the same tax year – handy if you want to spread across different platforms. Just don’t exceed the £20,000 total across all your ISAs.

Tax-free forever

Any gains, dividends, or interest you earn inside an ISA are tax-free – and they stay tax-free for as long as the money remains in the ISA wrapper. There’s no limit on how much your ISA can grow to.

Age requirement

You need to be 18 or over to open a Stocks & Shares ISA (16 for Cash ISAs). You also need to be a UK resident for tax purposes.

Index funds & ETFs – The r/UKPersonalFinance favourite. A single fund that tracks hundreds or thousands of companies. Low fees, instant diversification, minimal effort. This is what I use for most of my ISA.

Investment trusts – Similar to funds but structured as companies listed on the stock exchange. Some have been around for over 100 years. Scottish Mortgage is probably the most famous one.

Individual shares – Buy shares in individual companies, UK-listed or international. Higher risk than funds since you’re not diversified, but some people like picking their own stocks.

Bonds & gilts – Government and corporate bonds, either directly or through bond funds. Generally lower risk and lower return than shares.

In-specie transfer (as stock) – Your investments move across without being sold. No time out of the market, but takes longer and the new platform needs to support the same funds.

Cash transfer – Your investments are sold, cash is transferred, then you reinvest. Faster, but you’re out of the market during the transfer.

Under £20,000

Percentage-based platform fees are low at this level – 0.25% on £10,000 is just £25/year. But trading fees hit harder: a £5 dealing charge on a £100 investment is 5% gone before you start. Zero-fee platforms like Trading 212, Freetrade, and InvestEngine charge neither, though they typically offer fewer investment options or more basic customer service.

£20,000–£100,000

Percentage-based platform fees start to add up. A 0.25% fee on £50,000 is £125/year. Fixed-fee platforms charging £5-10/month start to look more competitive. FSCS protection covers up to £85,000 per provider.

£100,000+

Fixed-fee platforms are typically cheaper than percentage-based ones at this level. A flat £12/month beats 0.25% (which would be £250/year on £100k). Some people split across multiple providers to stay within FSCS limits.

A common approach

Some investors make regular contributions on a platform with no trading fees (like InvestEngine or Trading 212), then transfer to a cheap fixed-fee provider like Scottish Widows, Lloyds, or Halifax once the balance is large enough. You get free trades while building up, then minimal platform fees for long-term holding. ISA transfers keep the tax-free status intact.

Interest on uninvested cash – Any cash sitting in your account earns interest for the platform. Some platforms now share this interest with customers, but many keep it.

Foreign exchange fees – When you buy investments priced in dollars or euros, the platform converts your pounds and takes a cut (typically 0.15% to 1.5%). This adds up if you’re buying US shares or non-GBP denominated ETFs.

Wider spreads – The difference between buy and sell prices may be slightly wider than on platforms charging explicit fees.

Securities lending – Some platforms lend out your shares to other market participants and keep the fee.

Premium subscriptions – Free tier gets you in the door, then they upsell paid features like SIPPs, instant deposits, or better FX rates.

The basics

FSCS investment protection covers up to £85,000 per person, per firm. This hasn’t changed – though cash deposits in banks increased to £120,000 from December 2025, the investment limit remains at £85,000.

This is separate from cash deposit protection – you could claim both if the same financial group failed across both categories.

For FSCS to protect you, the firm must be authorised by the Financial Conduct Authority (FCA) or Prudential Regulation Authority (PRA), and the specific activity they’re carrying out must be regulated.

What FSCS covers

According to the FSCS website, they may be able to protect you if:

• A provider goes out of business and there’s a shortfall in the money or assets it’s holding for you
• You received bad advice from a regulated adviser that caused you to lose money

FSCS does not cover losses from poor investment performance – that’s market risk, not something the scheme protects against.

Protection varies by investment type

The FSCS investment protection checker shows that coverage depends on what you’re invested in:

Possibly protected: OEICs, Unit Trusts, Shares, Bonds, ETFs/Tracker Funds – but protection depends on the specific circumstances and whether the firm was carrying out a regulated activity.

Not protected: Cryptocurrency, P2P lending (the platform itself), E-money, NFTs.

The FSCS advises: “Ask your firm to confirm that the activity they are carrying out for you is a regulated activity and FSCS protected.”

Ring-fencing: your first line of defence

FCA-regulated platforms must follow rules called CASS (Client Assets Sourcebook) that require them to keep your money and investments separate from their own. This is called “ring-fencing” or “segregation”.

If a platform goes bust, your investments should still be there – held separately and waiting to be transferred to a new provider. FSCS is the backstop if something goes wrong with this ring-fencing (fraud, poor record-keeping, etc.).

Brands that share the same protection limit

The £85,000 limit applies per firm, not per brand name. Some platforms operate under the same authorisation – check the FCA Register to see if your providers are part of the same group.

What to check

The FSCS recommends three steps:

1. Check your provider is authorised by the FCA or PRA on the Financial Services Register
2. Be aware that the specific activity must be regulated for FSCS protection to apply
3. Ask your firm to confirm their FSCS protection status and what’s covered

How it works

Build on a percentage-fee platform – Use somewhere like Vanguard (0.15% platform fee, free trades) or Dodl (0.15%, free trades) for your regular monthly contributions. The percentage fee is tiny on a small balance, and you’re not paying £5 every time you invest.

Transfer to a fixed-fee platform for storage – Once the tax year ends, transfer your ISA to Scottish Widows, Lloyds, or Halifax (zero platform fee, £5/trade). You’re not trading there, just holding – so you pay nothing.

Repeat each year – Open a fresh ISA at Vanguard/Dodl in April, keep contributing monthly, transfer last year’s ISA to your holding platform.

InvestEngine – Zero-fee ETF platform. I use this for my main ISA and will probably open a SIPP here too.

IG Invest – No platform fees if you make 3+ trades per quarter. I use this for ISA investing.

Trading 212 – All-in-one trading platform. I use this for ISA, Cash ISA, and experimenting in a GIA.

Dodl – Simple investing by design. I use this for my Lifetime ISA.