As of 2015, there is no telephone number for Hotmail customer service. All Hotmail email accounts have been moved to the Outlook.com web platform. For users having trouble accessing their accounts, Microsoft has provided a webpage of information to help with the transition. The address of the webpage is http://windows.microsoft.com/en-us/windows/outlook-help.
The webpage covers several topics to assist all new Outlook.com users. There are videos, suggestions and best practices that cover the new web email system. If users need additional assistance, there is a link on the Hotmail webpage that provides help via an online chat system with a Microsoft representative.