What's a verification code, and why are they so important? Six-digit verification codes are a form of two-factor authentication, a process that helps keep your important online accounts secure.

Financial guru Martin Lewis is encouraging individuals to send a text message containing a five-digit code in order to reduce their mobile phone bills.

・ Text PAC to 65075 – This generates a unique porting authorisation code that allows customers to transfer their number to a new network.