Stonekeel

Which UK ISA platform is cheapest for you?

UK platforms charge either a percentage of your pot or a flat fee, and which is cheaper flips as your balance grows. Set your pot size to see the annual platform cost at each, cheapest first.

PlatformAnnual platform feeFee model
InvestEngineFree£0 (ETF-only)
Trading 212Free£0
XTBFree£0 (0.2% over £100k/mo turnover)
interactive investor£72Flat £5.99/mo (£14.99 over £100k)
Vanguard UK£750.15% capped £375; £4/mo under £32k
AJ Bell£1250.25% (funds)
Hargreaves Lansdown£1750.35% (funds)
Moneybox£237£1/mo + 0.45%

Platform fee only, for funds/ETFs (excludes dealing and the funds' own charges). Percentage platforms are cheapest for small pots; a flat fee wins once the pot is large enough, which is the crossover to watch. InvestEngine and Trading 212 are ETF/stock-focused. Figures are illustrative and verified as of 2026, so check current terms.

Want the full picture? Read best broker for a Stocks and Shares ISA, or compare platforms on everything else with Brokerlens.