Abstract: Methods and apparatuses for improving the privacy and security of wireless communications by automatically preloading an electronic subscriber identity module (eSIM) profile associated with a temporary service plan prior to making a phone call to a particular phone number and by leveraging eSIM profiles to enable number portability are described. Before placing a call to a new or unknown phone number, a mobile phone may automatically identify a temporary eSIM profile from a pool of eSIM profiles based on a geographic location of the mobile phone and/or the particular phone number to be called. The temporary eSIM profile may be loaded into an embedded universal integrated circuit card (eUICC) of the mobile phone prior to placing the call to the new or unknown phone number.