Premium Bonds Calculator

Our Premium Bonds calculator estimates prize chances and expected return. Prize rate: 4.40% tax-free (2026). Odds: 22,000 to 1 per £1 bond per month. Maximum holding: £50,000.

Enter your premium bonds holding and select how long to hold them. Premium bonds do not pay guaranteed interest — instead, each £1 bond is entered into a monthly draw. The prize fund is equivalent to an annual tax-free rate (the current prize fund rate is set by NS&I and reviewed periodically). The calculator uses the official prize fund rate and your holding to estimate your expected annual prize income on a probability basis. However, because prizes are random, any individual saver may receive significantly more or less than the expected return in any year. Premium bonds are most appropriate for higher and additional rate taxpayers who have used their ISA allowance and whose savings interest would otherwise be taxed — the tax-free prize equivalent rate compares favourably against taxable savings for this group.