TL;DR
UK investment platforms differ on fee structure (percentage versus flat fee), investment range, and account features. The fee model that suits a portfolio depends mainly on portfolio size: percentage fees suit smaller portfolios, flat fees suit larger ones. This article compares the main UK platforms on a like-for-like basis.
Key facts
- UK retail investment platforms must be authorised by the Financial Conduct Authority.
- Platform fees typically take one of two forms: a percentage of assets (often 0.25 to 0.45 percent) or a flat annual charge.
- The FSCS investment limit of GBP 85,000 per firm applies if a platform fails and money or assets are missing.
- Many platforms cap percentage fees once a portfolio exceeds a certain size, often around GBP 250,000 to GBP 1,000,000.
- Dealing charges per trade vary, with most major UK platforms charging zero on fund deals and a flat fee on equity trades.
How UK platforms make money
A UK investment platform holds the wrapper (ISA, SIPP, GIA), settles trades, holds the assets in nominee, and provides reporting. Platforms charge a platform fee plus, in some cases, dealing charges, foreign exchange charges, and exit fees. The underlying fund managers charge a separate Ongoing Charges Figure that is independent of the platform.
Percentage versus flat fee
Two main fee models exist. Percentage fees scale with portfolio size, typically 0.25 to 0.45 percent per year, with caps that vary by wrapper. Flat-fee platforms charge a fixed annual amount regardless of portfolio size, often between GBP 100 and GBP 240 per year per wrapper.
The crossover point at which a flat fee becomes cheaper than a percentage fee depends on the specific fees of each provider, but the general principle is that small portfolios are cheaper on percentage fees while large portfolios are cheaper on flat fees.
Investment range
Major UK platforms differ in what they offer. Full-service platforms allow shares listed across multiple international exchanges, thousands of funds, ETFs, investment trusts, gilts, and corporate bonds. Restricted platforms (such as those run by a single fund manager) may only offer that manager's funds. A SIPP-only platform may have different fund availability from an ISA platform.
Features that matter beyond fees
Service features include execution quality, mobile app functionality, model portfolios, fractional share dealing, regular investment without dealing charges, foreign exchange spread, and customer service responsiveness. The FCA Consumer Duty, in force since 31 July 2023, requires platforms to deliver fair value to retail customers.
Wrapper coverage
Most UK platforms offer at least an ISA, a SIPP, a Junior ISA, and a GIA. Lifetime ISAs are available on a smaller subset of platforms. Innovative Finance ISAs are restricted to specialist providers.
Switching providers
UK platforms must facilitate in-specie transfer of holdings to another provider. Exit fees per holding were historically common but have largely been removed following FCA scrutiny. Cash transfers are typically free; in-specie transfers may take several weeks.
Regulatory protection
Platforms must hold client money under FCA CASS rules, segregated from the firm's own assets. The Financial Services Compensation Scheme covers investment claims up to GBP 85,000 per firm where the firm fails and client money or assets are missing.
Tax wrapper coverage across platforms
Most UK platforms offer at least an ISA, a SIPP, a Junior ISA, and a GIA. Lifetime ISAs are available on a smaller subset of platforms (around half of major retail platforms). Innovative Finance ISAs are restricted to specialist providers. Business pension wrappers (workplace personal pensions for small employers) are offered by a smaller set of platforms specialising in that segment.
The wrapper range matters when consolidating. A saver wanting to combine an ISA, a SIPP, a JISA for a child, and a Lifetime ISA into a single platform must verify that all four wrappers are available; not every platform offers the full set. The administrative simplicity of a single platform login is the main consolidation benefit.
FSCS protection and platform failure
UK investment platforms operate under FCA authorisation and must hold client money and assets under the FCA's Client Assets Sourcebook (CASS) rules. Client money is held in segregated bank accounts; client assets are held in nominee accounts segregated from the platform's own assets. The Financial Services Compensation Scheme covers investment claims up to GBP 85,000 per firm where the firm fails and client money or assets are missing.
Platform failures are rare but not unknown. The 2018 collapse of Beaufort Securities led to FSCS compensation for affected clients; the SVS Securities special administration in 2019 produced similar outcomes. In each case, segregated nominee structures generally protected the underlying client assets, with FSCS covering any shortfall in client money or expenses.
Switching between platforms
Platforms must facilitate in-specie transfer of holdings to another provider under the Origo electronic transfer infrastructure where supported. Modern UK platforms typically complete transfers within 4 to 12 weeks; transfers requiring paper processing or non-Origo schemes can take longer. The FCA has banned exit fees per holding on most retail platform products following the 2018 to 2019 Investment Platforms Market Study.
Where the receiving platform does not support an asset held on the ceding platform, the saver must either sell the asset before transfer (incurring potential CGT outside an ISA or SIPP) or accept that the asset stays on the original platform. Some specialist holdings (such as listed shares from less common exchanges or specific fund share classes) can have transfer compatibility issues.
The percentage versus flat fee breakeven point
The most important fee architecture choice is between percentage-based platforms and flat-fee platforms. Percentage-based platforms charge an annual fee proportional to assets held, typically 0.15 to 0.45 percent per year on the platform layer, often with caps once the portfolio reaches a threshold (commonly GBP 250,000 to GBP 500,000). Flat-fee platforms charge a fixed annual amount regardless of portfolio size, typically GBP 100 to GBP 240 per wrapper.
The breakeven point depends on the specific provider fee schedules. For a typical comparison between a 0.25 percent percentage platform and a GBP 200 flat fee platform, the breakeven is around GBP 80,000 of assets. Below GBP 80,000, the percentage platform is cheaper. Above GBP 80,000, the flat fee platform is cheaper, with the differential growing rapidly at higher balances.
For a saver consolidating multiple legacy pensions into a SIPP and expecting the balance to grow over decades, the choice of fee structure can compound to substantial total cost differences. A GBP 500,000 portfolio on a 0.25 percent platform pays GBP 1,250 per year; on a GBP 200 flat fee platform, GBP 200 per year. Over 20 years, the cumulative difference exceeds GBP 20,000 even ignoring growth on the saved fees.
Underlying fund OCFs and total cost
The platform fee is one layer. The underlying fund OCF is the other. Fund OCFs are deducted from the fund's daily NAV calculation, so the investor sees them implicitly through fund performance rather than as a separate charge. A typical UK retail investment portfolio's total cost runs from 0.20 percent (cheap index trackers on a low-cost platform) to 1.50 percent or more (active funds on a percentage-fee platform).
Some funds have multiple share classes with different OCFs. The 'clean' (institutional) share class on a major fund typically has an OCF 0.50 to 0.75 percentage points lower than the 'retail' (commission-paying) share class. Most modern UK platforms make clean share classes available to retail investors; older platforms or arrangements may still use retail share classes.
FX charges and overseas dealing
Buying overseas-listed securities incurs an FX charge on conversion between sterling and the trading currency. UK platforms typically charge 0.25 to 1.5 percent FX spread depending on the deal size and platform. For a saver holding US-listed shares or ETFs, the FX charge can be a meaningful cost.
Many platforms offer USD and EUR cash holding options, allowing the saver to keep foreign currency proceeds from sales without converting back to sterling. This is useful for dividend reinvestment in the same currency and for managing FX exposure. The Open Banking and modern platform infrastructure has made multi-currency cash management more accessible.
Customer service and execution quality
Platform features beyond fees include execution quality, mobile app functionality, model portfolios, fractional share dealing (allowing purchases of partial shares), regular investment without dealing charges, and customer service responsiveness. The FCA Consumer Duty, in force since 31 July 2023, requires platforms to deliver fair value to retail customers across all these dimensions.
The Consumer Duty has driven greater transparency in fee disclosure and required platforms to demonstrate the value delivered for the fees charged. Annual Value Assessment reports are published by each platform's Independent Governance Committee or equivalent. The reports are useful sources for comparing platform value.
Disclaimer
This article provides general information about UK investment platforms and is not personal financial advice or a recommendation of any specific provider. Fees and features change; readers should check current published charges before opening an account.
Frequently asked questions
Which UK platform is cheapest?
The cheapest platform depends on portfolio size, wrapper, and trading frequency. Percentage-fee platforms typically suit smaller portfolios; flat-fee platforms suit larger ones.
Are platform fees tax-deductible?
Platform fees paid from inside an ISA or SIPP are simply deducted from the wrapper balance with no tax effect. Fees on a GIA can sometimes be paid externally to keep assets working.
What happens if a platform fails?
Client assets are held in nominee accounts segregated from the platform. The FSCS covers any shortfall up to GBP 85,000 per firm where money or assets are missing.
Can the same holdings be moved between platforms?
Yes, via in-specie transfer. The holdings remain invested through the transfer process, though dealing in transferring assets may be suspended for a short period.
Do platforms charge for buying funds and shares?
Most UK platforms charge zero on fund deals. Share, ETF, and investment trust trades typically incur a flat dealing fee, with regular investment schemes offering lower charges for set monthly dates.
Frequently asked questions
Which UK platform is cheapest?
The cheapest platform depends on portfolio size, wrapper, and trading frequency. Percentage-fee platforms typically suit smaller portfolios; flat-fee platforms suit larger ones.
Are platform fees tax-deductible?
Platform fees paid from inside an ISA or SIPP are deducted from the wrapper balance with no tax effect. Fees on a GIA can sometimes be paid externally to keep assets working.
What happens if a platform fails?
Client assets are held in nominee accounts segregated from the platform. The FSCS covers any shortfall up to GBP 85,000 per firm where money or assets are missing.
Can the same holdings be moved between platforms?
Yes, via in-specie transfer. Holdings remain invested through the transfer, though dealing may be suspended briefly.
Do platforms charge for buying funds and shares?
Most UK platforms charge zero on fund deals. Share, ETF, and investment trust trades typically incur a flat dealing fee.
