A board of directors is an organisation comprised of individuals who are responsible for the management, control, and direction of that organization. They are accountable for the legal obligations and accountability of a company. This means that if they fail meet their fiduciary duty and are found to be in breach, they could be personally held accountable.
An advisory board, on the other hand is a group of people who offer guidance and mentorship on how a business should run. They provide more direct and practical advice and tend to focus on growth, strategy and development, not reporting, risk management, governance and avoiding risks that could be detrimental to the business.
Ideally, an organization should clearly define the purpose of its advisory board in all official documents like meeting minutes, as well as in oral communications to avoid confusion. This will ensure that they do not accidentally cross over into the territory of a board of directors and have grave legal consequences if they fail to meet their fiduciary obligation.
In reality, this distinction may be blurred and organisations may refer to their advisory board as “the Board.” It is recommended making it clear in writing to avoid confusion or accidental mistakes. A formal statement that defines the role of an advisory board can help to minimise confusion among the people involved. This is especially beneficial when board members have been previously on a board or are new to the organization.
https://theirboard.com/whats-the-difference-between-the-board-of-directors-and-an-advisory-board/