Area Code 58 – Gorica/Koper/Postojna

Overview of Area Code +386 58

Area code 58 is a geographic National Destination Code (NDC) within the Slovenian national numbering plan, assigned to the western part of the country, specifically the region encompassing the cities of Nova Gorica, Koper, and Postojna. This area code is part of the E.164 international dialing format, where the full international number begins with +386 58 followed by the subscriber's local number. The code serves both fixed-line PSTN and VoIP services that are geographically allocated to this region.

Geographic Coverage and Administrative Jurisdiction

The 58 area code covers the Slovenian Littoral and part of the Inner Carniola statistical regions. It includes the municipalities of Nova Gorica, Koper, Postojna, and their surrounding settlements. These areas are known for their proximity to the Italian border and the Adriatic coast, making them important commercial and tourist hubs. The administrative jurisdiction falls under the respective municipal governments, but telecommunication services are regulated by the Agency for Communication Networks and Services of the Republic of Slovenia (AKOS).

Dialing Formats and Instructions

For local callers within Slovenia, dialing a number in the 58 area code requires the trunk prefix 0 followed by the area code and the subscriber number. For example, a local call to a fixed line in Nova Gorica would be dialed as 05 8XX XX XX (where the 0 is the national trunk prefix). However, when calling from abroad, the international access code (typically 00 or +) is used, followed by the country code 386, the area code 58 without the leading zero, and the subscriber number. For instance, a caller from Germany would dial 00 386 58 XXX XXX or +386 58 XXX XXX.

Number Structure and Overlay Considerations

Slovenian fixed-line numbers have a variable length, typically 8 digits in total when including the area code. In the 58 area, subscriber numbers are usually 6 digits long, making the complete national significant number (NSN) 8 digits. There are no overlay codes in this region; the 58 code is unique to the area. However, due to number portability, a subscriber may retain their 58 number even if they move to a different geographic area, which can occasionally lead to non-geographic usage of the code.

Caller Instructions

For local callers within Slovenia, always include the trunk prefix 0 when dialing a number in the 58 area code, even if calling from a mobile phone. For international callers, omit the leading 0 and use the +386 country code. It is also important to note that calls to Slovenian fixed lines are typically charged at standard national rates, while international rates vary by carrier. For emergency services, dial 112, which is free from any phone.