Tufts Health Plan and Harvard Pilgrim Health Care, eight years after their first known attempt, announced plans to combine the organizations to become one of the region’s largest nonprofit health services organizations. The combined entity will serve nearly 2.4 million members in Massachusetts, Maine, Connecticut, New Hampshire, and Rhode Island, and offer employer-sponsored plans, Medicare and Medicaid plans, and Qualified Health Plans in an effort to keep high-quality health care accessible and affordable. The new board of directors will contain equal representation from both organizations, and the combined organization will retain the CEO/president of each organization. The contemplated agreement has been unanimously approved by both boards and is subject to state and federal regulatory approvals.