Cash ISA vs stocks and shares ISA: the decision most people postpone
Every UK adult has a £20,000 annual ISA allowance that resets on 6 April. Cash ISAs pay interest with no income tax on the earnings. Stocks and shares ISAs invest in funds or shares with gains and dividends sheltered from capital gains tax and income tax. The allowance cannot be carried forward: money not used by 5 April is lost for that tax year.
In a high-interest-rate environment, Cash ISAs become more attractive because the personal savings allowance (£500 for higher-rate taxpayers) is quickly exhausted by other savings accounts. Once you exceed the PSA, savings interest is taxed at your marginal rate -- an ISA sidesteps this entirely.
Model the long-term growth of your savings with the savings goal tool and see how compound interest builds over time with the compound interest calculator.
Premium Bonds: the misunderstood savings product
Premium Bonds pay no interest. Instead, your money is entered into a monthly prize draw where the equivalent of a 4.65 % annual prize rate (as of 2024) is distributed as tax-free prizes ranging from £25 to £1 million. The median expected return for a full £50,000 holding is around £185 per month -- equivalent to 4.44 % per year.
The catch: your return is not guaranteed. With a small holding (under £5,000), the expected prize in any given month is £0, and the statistical median return is below the headline rate. Premium Bonds make most sense for higher earners with large sums whose savings income would otherwise be taxed, or for those who enjoy the lottery element.
SIPP: the most tax-efficient wrapper for long-term savings
A Self-Invested Personal Pension (SIPP) adds 20 % basic-rate tax relief to every contribution automatically, effectively turning a £800 contribution into £1,000. Higher and additional-rate taxpayers can claim a further 20 to 25 % back through self-assessment. The money grows free of income tax and capital gains tax, but cannot be accessed before age 57 (rising to 57 in 2028).
For retirement savings, a SIPP almost always outperforms an ISA on a tax-adjusted basis for higher earners -- but the 25 % tax-free lump sum at withdrawal and the illiquidity are key factors to weigh.