Data Care Act of 2018 This bill imposes various duties on online service providers with respect to to their handling of user data, including duties to (1) reasonably secure sensitive data from unauthorized access, (2) refrain from using such data in a way that will result in reasonably foreseeable harm to the end user, and (3) not disclose individual identifying data to another party unless that party is also bound by the duties established in this bill. The bill authorizes the Federal Trade Commission and specified state officials to take enforcement actions with respect to breaches of such duties.