Savers are being urged not to overlook a range of tax-free perksRory Poulter07:58, 24 May 2026British savers are being urged not to squander their annual £20,000 Isa allowance as experts warn that significant rule changes are on the horizon for millions.‌Consumer group Which? warns that many households are overlooking a host of hidden tax benefits linked to Individual Savings Accounts - at a time when frozen tax thresholds are pulling more workers into higher tax bands. The alert comes as rivalry amongst banks and building societies heats up, with the number of cash Isa deals reaching a record high this spring.‌According to Moneyfacts data, there were 712 cash Isa accounts available on April 1, 2026 - the highest figure ever recorded. Average instant-access cash Isa rates also climbed from 2.61% to 2.73% AER.‌However, experts argue the real draw is not simply tax-free interest - it is the increasing necessity of shielding savings from the taxman as fiscal drag continues to tighten its grip. Office for Budget Responsibility forecasts suggest that by 2030-31, a further 4.8 million people will be pulled into the higher-rate tax bracket as income tax thresholds remain frozen while wages keep rising.This means savers who previously paid 20% tax on savings interest could ultimately face a 40% blow instead. Matthew Jenkin, senior writer at Which? Money, said savers should not underestimate the long-term value of protecting money inside an Isa wrapper. He drew attention to lesser-known Isa advantages that many households consistently fail to take advantage of.‌Protection from Capital Gains TaxProfits generated within a stocks and shares Isa are completely exempt from CGT, unlike investments held outside the tax-free wrapper where gains exceeding £3,000 become taxable in the 2026-27 tax year. Experts suggest investors can also utilise a "Bed and Isa" approach - disposing of investments held outside an Isa before reacquiring them within the tax-free account.Cash Isas outperform many standard easy-access savings accountsMoneyfacts data reveals the average instant-access cash Isa paid 2.73% on 1 April compared with 2.44% for non-Isa accounts. On a £10,000 balance, this could leave savers approximately £29 better off over a year. However, experts cautioned that fixed-rate savings accounts can still provide superior deals compared to fixed cash Isas.‌The research discovered one-year and multi-year fixed savings accounts have typically outperformed equivalent Isa products in recent years. Among the recent market-leading offers highlighted were a 5% easy-access saver from Cahoot and a 4.52% one-year fixed cash Isa from Investec.Content cannot be displayed without consentLooming restriction planned for April 2027Under proposals announced by the Government, under-65s will only be able to hold £12,000 in cash within an Isa. Anyone wanting to use the full £20,000 allowance would need to place the remaining £8,000 into investments through a stocks and shares Isa.Article continues belowInheritance advantages attached to IsasBereaved spouses and civil partners are able to inherit both the savings and the tax-free status through an Additional Permitted Subscription allowance, which was introduced in December 2014.Flexible IsasThese savings accounts can be particularly handy for emergency funds, as withdrawals can be replaced within the same tax year without affecting the annual allowance.Younger savers with student loans could benefitAs Isa interest is tax-free, it does not count as taxable savings income in self-assessment calculations - potentially helping borrowers steer clear of higher student loan repayments.