According to the BBC, over 400,000 savers and investors will see their returns tumble as state owned NS&I lowers rates on tax-free Individual Savings Accounts (ISAs).
Interest rates are being cut from 1.5% to 1.25%, the lowest rate since 2008 when the products were first introduced.
The organisation was forced to reduce rates due to the success of Pension Saving Bonds.
Government rules and regulations means that NS&I is not allowed to attract too much cash, at the expense the UK tax-payer.