The unified civil number (Bulgarian: Единен граждански номер, ЕГН, romanized: Edinen grazhdanski nomer, EGN) is a 10-digit unique number assigned to each Bulgarian citizen.
The uniform system for civil registration and administrative service of population (Bulgarian: Единна система за гражданска регистрация и административно обслужване на населението; abbreviated: ЕСГРАОН, ESGRAON) regulates the EGN system.
For people born between 1900 and 1999 the middle digits are the month number: YYMMDD.
In order to easily cross borders criminals have been known to change EGNs.
Using the EGN system for identification raised some privacy concerns, though they are officially considered personal information and are protected by law.