For a child in elementary school, avoiding the principal is paramount. But for folks looking toward retirement, seeking The Principal may be wise. Founded in 1879, Principal Financial Group (or The Principal) is a top administrator of employer-sponsored retirement plans, offering pension products and services, as well as mutual funds, annuities, asset management, trust services, and investment advice. Its insurance segment provides group and individual life and disability insurance and group dental and vision coverage. Subsidiary Principal Bank offers online banking. PFG boasted 19.1 million customers and $527.4 billion in assets under management at the end of 2015.