UK tax-advantaged accounts (Stocks and Shares ISA, pension contributions) offer some of the highest guaranteed returns available to most earners — through tax relief, employer matching, and tax-free growth. Most adults use a small fraction of available allowance, leaving substantial money on the table.
The hierarchy
Capture full employer pension match first (free money, 100% return). Maximise ISA next (£20,000/year, tax-free growth). Then additional pension contributions for tax relief at marginal rate. Then general investment accounts after these are filled.
What 'maximise' actually means
Hit your match cap on workplace pension. Aim to fully use the £20,000 ISA allowance even if you have to spread it across the year. Make additional pension contributions if you're a higher-rate taxpayer with room.
Most workers will compound tens of thousands more over a career by deliberately using tax-advantaged accounts over neutral ones. The tax efficiency adds 1-2% annually to returns — substantial over decades.