Post Office Junior ISA is managed by Post office Ltd.

Post Office Ltd is a retail post office company in the United Kingdom that provides a wide range of products including postage stamps and banking to the public through its nationwide network of post office branches. The company is owned by UK Government Investments.

The Post Office provides credit cards, current accounts, insurance products, mortgages and personal loans through the Post Office Money umbrella brand which was launched in 2015. Most Post Office Money branded products are provided by Bank of Ireland (UK) plc with Post Office Ltd acting as an appointed representative and credit broker. However, with the sale of the Bank of Ireland’s UK assets to Jaja Finance in 2019,  Post Office branded Credit Cards are now issued by Capital One UK.