The FSCS (Financial Services Compensation Scheme) exists to protect people in the UK who use financial services, such as bank accounts, mortgages and insurance policies.

Their website says this about the money you have in your savings account:

If you hold money with a UK-authorised bank, building society or credit union that fails, we’ll automatically compensate you up to £85,000 per eligible person, per bank, building society or credit union.

If you have money in multiple accounts with multiple banks that are part of the same banking group (and share a banking licence) we have to treat them as one bank. This means that in the event of a firm failure, our £85,000 compensation limit applies to the total amount you hold across all these accounts, not to each separate account.

That means that, as your Stream Save account uses Investec Bank Plc, up to £85,000 of your money is protected in total, across all of your accounts with them. 

You can find out more about the FSCS here.