An Eligible Automatic Contribution Arrangement (EACA) is a type of retirement plan feature where employees are automatically enrolled to contribute part of their paycheck into the company’s retirement plan unless they choose to opt out. EACAs must meet specific rules, such as giving employees advance notice before automatic contributions begin and allowing them to withdraw those contributions within a short window if they change their mind. These plans are designed to encourage more people to save for retirement by making the process easier and more hands-off, while also giving employers the option to simplify plan administration.