What is the minimum age for opening a Stock and Shares ISA?

The minimum age for opening a Stock and Shares ISA is 18. This age threshold aligns with the legal capacity to enter into a financial contract in the UK, which is crucial for investing and managing financial products. Individuals must be at least 18 years old to both open and contribute to a Stock and Shares ISA, ensuring that they have reached a level of maturity where they can make informed financial decisions.

While the option of 16 might seem appealing, it pertains to Junior ISAs, which are specifically designed for minors. Once individuals reach 18, they can transition to adult ISAs (including Stock and Shares ISAs) to further their investment options and financial independence. The other options listed (21 and 20) are not relevant as the ISA framework is specifically structured around the age of 18 as the starting point for adult investment accounts.