+378 Which country’s code? +378 Where is the code? Home › Forums › International codes › +378 Which country’s code? +378 Where is the code? This topic contains 0 replies, has 1 voice, and was last updated by yönetim 1 year, 8 months ago. Viewing 1 post (of 1 total) Author Posts 12/03/2019 at 02:57 #2183 yönetimKeymaster You must use the +378 code before your phone calls. The phone code for making international calls starting with +378 belongs to whom. +378 San Marino If you dial your phone number by dialing this code, you can make your international call without error. Author Posts Viewing 1 post (of 1 total) You must be logged in to reply to this topic.