To call about an existing reservation, use the United customer service number 1-800-UNITED-1 (+1-833-730-7585 ).For reservation assistance in the U.S. and Canada, call +1-833-730-7585 .For those with accessibility issues, use United’s 24-hour Accessibility Desk, which can be reached at +1-833-730-7585 from the United States and Canada.Can you chat with United Airlines?United Airlines has two live chat features. One called MileagePlus Assistant offers a chance to discuss MileagePlus-related subjects on demand.You can also use the Virtual Assistant chat for other topics such as reservations, ba