How to Choose a UK Investing Platform
A 5-question framework. Answer these and the right platform is usually obvious.
The UK has a dozen serious investment platforms. They all let you hold ISAs and SIPPs and buy similar funds. The differences are in pricing structure, range, and user experience — and the right answer depends almost entirely on you, not the platform.
Question 1 — How big is your pot?
This is the single most important question because UK platform pricing splits cleanly between percentage-fee and flat-fee.
• Under £20k — go free or near-free. Trading 212, InvestEngine, Freetrade.
• £20k–£60k — percentage platforms still cheap. AJ Bell (0.25%), Vanguard (0.15%, Vanguard funds only).
• £60k–£100k+ — flat-fee starts to win. Interactive Investor (£11.99/mo), iWeb (£0/yr, £5/trade).
The break-even between AJ Bell's 0.25% and II's flat fee is around £60k. Above that, every extra £1,000 saves you £2.50/year on the flat fee.
Question 2 — What do you want to hold?
• Funds (OEICs, unit trusts) — most platforms support these. Vanguard only offers Vanguard's own.
• ETFs — universal support; some platforms (Trading 212, InvestEngine) let you fractionally invest from £1.
• Individual UK shares — supported by HL, AJ Bell, II, Trading 212, Freetrade.
• US stocks — needs FX. Trading 212 (0.15% FX) is the cheapest mainstream option.
• Investment trusts, gilts, bonds — full-service platforms only (HL, AJ Bell, II).
If you only want a single global ETF, almost anyone works. If you want gilts or US stocks, your shortlist shrinks.
Question 3 — How often will you trade?
• Buy and hold (1–5 trades/year) — dealing fees barely matter. Pick on platform/fund fee.
• Active (10+ trades/year) — you'll feel £10/trade dealing charges. Trading 212 (free) or II (free monthly trade) win.
• Day-trader — Trading 212, IBKR, or eToro. But statistically you'll lose money — don't do it.
Question 4 — Do you need an ISA, SIPP, or both?
Most platforms offer both, but pricing differs:
• ISA only — Trading 212, InvestEngine, Freetrade are great
• SIPP only or both — Some “free” platforms charge for SIPP. AJ Bell, HL, II, Vanguard all do both well.
• JISA (Junior ISA) — fewer platforms support it. AJ Bell, HL, Fidelity, Vanguard do.
Question 5 — How important is the user experience?
This is subjective but real. App quality varies enormously:
• Best apps: Trading 212, Freetrade, InvestEngine
• Best web platforms: AJ Bell, HL, Vanguard
• Worst UX (still functional): iWeb, II
If you'll only ever check it twice a year, ugly is fine. If you check it weekly, UX matters.
The 5-second answers
• “I'm new and have £5k” → Trading 212 or InvestEngine
• “I want a SIPP, £20k pot” → AJ Bell or Vanguard
• “I'm at £150k, buy and hold” → Interactive Investor or iWeb
• “I want US stocks” → Trading 212 (cheapest FX)
• “I want everything in one place” → AJ Bell or Hargreaves Lansdown
Compare line-by-line in our broker comparison and dig into hidden costs in the platform fees deep dive.
