Platform review

Interactive Investor ISA Review 2026

UK's second-largest investment platform, charging a flat monthly subscription rather than a percentage fee. This makes it excellent value for larger portfolios but expensive for smaller ones.

Founded 1995
Flexible ISA No
FSCS Protected
Fees updated 2026-04-15

ISA fees at key portfolio sizes

Portfolio Funds ETFs Shares

Monthly trading assumed. Verify at Interactive Investor

Accounts & features

Stocks & Shares ISA
SIPP
GIA
Junior ISA
Flexible ISA
Fractional shares
Regular investing
Mobile app
FSCS protected✓ (up to £85,000)

Overview

Interactive Investor (ii) is the UK’s second-largest direct investment platform, and the leading flat-fee option for UK investors. Instead of charging a percentage of your portfolio, ii charges a fixed monthly subscription — making it dramatically cheaper than percentage-based platforms for larger portfolios.

The flat fee advantage

At £11.99/month (£143.88/year) for an ISA, ii’s cost is fixed regardless of whether you have £50,000 or £500,000 invested. For a £100,000 portfolio, this compares to £450/year at Hargreaves Lansdown — a saving of over £300/year.

The subscription includes 12 free trades per year. Additional trades cost £5.99 each.

Who is ii best for?

Who might prefer alternatives?

Verdict

ii is the natural upgrade from HL for investors whose portfolios have grown. The crossover happens around £50,000 for most funds investors. Use our calculator to find your exact crossover point.

Open a Interactive Investor ISA

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