No, you cannot gain entry to a United Club location if you are not flying on United. As of Nov. 1 2019, admittance to a United Club location with a United Club membership card or one-time pass must be accompanied by a same-day boarding pass for travel on United, Star Alliance, or a contracted-partner-operated flight. This is in addition to the requirement of showing a government-issued photo ID, such as a driver’s license, passport, or military ID.