ISA & Investment Guides | PlatformCompare

Plain-English guides to UK ISAs, SIPPs and investment platforms. Written from experience, not for search engines.

ISA rules
Can You Hold Multiple ISAs? The 2026/27 Rules Explained
3 min · April 2026
Platform fees
Percentage vs Flat Fee Investment Platforms — Which Is Right for You?
5 min · April 2026
Cheapest ISA
The Cheapest Stocks & Shares ISA by Portfolio Size (2026)
5 min · April 2026
ISA fees
The ISA Fee Crossover Point — Why Portfolio Size Changes Everything
4 min · April 2026
Platform switching
When Does It Make Sense to Leave Hargreaves Lansdown?
5 min · April 2026