Walmart's New Health Care Policy Shifts Burden To Medicaid, Obamacare: Walmart, the nation’s largest private employer, plans to begin denying health insurance to newly hired employees who work fewer than 30 hours a week, according to a copy of the company’s policy obtained by The Huffington Post. Under the policy, slated to take effect in January, Walmart also reserves the right to eliminate health care coverage for certain workers if their average workweek dips below 30 hours -- something that happens with regularity and at the direction of company managers.