Savings in cash ISAs increased to £70 billion as savers seized higher rates, but are the best offers going away?

When interest rates in the UK rose to 525 percent in 2023–2024, nearly 10 million people invested in cash ISAs However, a number of reductions may mean that inflation is now eroding your savings

According to recent government statistics, savers flocked to cash ISAs last year to benefit from some of the highest interest rates available for savings since the financial crisis.

According to HMRC data, Cash ISA subscriptions increased by 67 percent, or £27.9 billion, during the 2023 - 2024 tax year. As a result, 69.5 billion was invested in cash ISAs overall for the year.

Money invested in stocks and shares in the ISA increased by a much smaller 11 percent, or 3 points 1 billion, for a total of 31 points 1 billion.

Early 2024 - 2025 dash-to-cash ISA stuffing is not reflected in these numbers. At this point, there were rumors that chancellor Rachel Reeves might reduce the cash ISA allowance before the Spring Statement. According to some, the cap might be as low as £5,000. The next HMRC report is probably going to show another spike in cash ISA take-up, as billions were hastily parked into cash at that time.

Rather, the 2023 - 2024 spike was caused by an increase in the base rate set by the Bank of England, which raised the interest rates available for cash ISAs.

The managing director of the investment platform Bestinvest, Jason Hollands, stated: "In 2023 - 2024, over 90.9 million people signed up for cash ISAs, the most in eight years. Given that UK interest rates increased to 5 percent that year, the highest level since 2008, this was not surprising.

According to Rachael Griffin, a tax and financial planning specialist at Quilter, increased interest rates have "clearly made cash ISAs more appealing" by providing returns that haven't been seen in more than ten years. The "temporary reprieve" is what she added, though.

"With the Bank of England expected to hold today before eventually cutting, the generous cash deals of the past year are unlikely to last," she said, adding that rates had already begun to drift lower.

Reductions in rates of cash savings.

Since the Bank started reducing rates in August 2024, Moneyfacts' analysis shows that the Bank of England's base rate cut to 4 percent last month has triggered a series of savings rate reductions.

Since August 2025 began, the average easy access savings rate has decreased by 0.08%, from 2point 68 to 2point 60, and the average easy access ISA rate has decreased by 0.08%, from 2point 90 to 2point 82.

Month-over-month, the Moneyfacts average savings rate dropped from 3 percent to 3 percent in September. It is below 4.29 percent in September 2023 and 4.8 percent since September 2024. In January 2024, the rate was last higher than 4 percent (4.04 percent).

Savings suffer when the Bank of England Base Rate is lowered, and the August 0.25 percent cut has not been an exception, according to Rachel Springall, a finance expert at Moneyfacts. Overall, savings rates are still declining.

What is the impact of inflation on cash savings?

Quilters Griffin advised savers to keep in mind that while cash offers temporary security, it produces long-term stagnation.

This is due to the fact that cash rates that are unable to keep pace with inflationwhich is currently 3point 8 percent, almost twice the Bank of England's 2 percent targetare gradually losing value.

Griffin explained, "Investments have a far better chance of outpacing inflation and increasing wealth in real terms, while inflation will gradually erode the value of money left sitting in cash."

Nevertheless, regardless of rate reductions, savers wishing to shield their money from taxes will continue to pursue ISAs. Because of fiscal drag, basic rate taxpayers who move up into the higher-rate tax bracket at 40 percent will see their Personal Savings Allowance (PSA) cut in half, from £1,000 to £500.

According to Springall, "this will only increase demand for ISAs, but the future of the cash ISA allowance is still up in the air as rumors continue to circulate for a review in the upcoming Budget."

Could the ISA limit be reduced to cash?

It appears that the chancellor's plans to reduce the Cash ISA allowance have been put on hold for the time being, but this does not mean that ISA reform is entirely off the table for the rest of this parliament.

It should be mentioned, Hollands stated: "A number of former members of the Resolution Foundation, a think tank that had previously supported capping ISAs at £100,000 per individual, are currently holding prominent positions in the government.

"Considering the increasingly onerous tax burden in the UK, with significantly reduced annual exemptions for dividends and capital gains and higher rates of CGT introduced at last year's Budget," he said, "ISAs should not be taken for granted."

Those who are able to use ISAs to shield their wealth from taxes should do so as completely as possible, Hollands continued, since the tax environment is only going to get harder in the near future due to the hole in the public finances.