- Do not dial a leading ‘0’ in the international call sequence – it is only used in North Korea for domestic long distance calls and domestic calls to a mobile phone.
- A leading '+' in the phone number means 'dial your country's exit code'.
- Calling from a mobile phone: dial from on the country where you're currently located.
- Calling from a VoIP or satellite phone: dial from on the country where the phone is registered.
‘0’ is used as a trunk prefix used when calling within North Korea.
North Korean phone numbers are six to ten digits.
The first one to three digits is an area code representing a geographic part of the country.
Many phone numbers within North Korea are inaccessible outside of the country (or when calling within the country). Phone numbers that being with 2 381 can usually make and receive international calls.
’00’ is used as an exit code when dialing an international phone call from North Korea.
- ITU (International Telecommunications Union) – United Nations specialized agency for information and communications technologies.
- International Telecommunications Union – DIALLING PROCEDURES (INTERNATIONAL PREFIX, NATIONAL (TRUNK) PREFIX AND NATIONAL (SIGNIFICANT) NUMBER) (IN ACCORDANCE WITH ITU-T RECOMMENDATION E.164 (11/2010)) – A collection of dialing procedures for all countries and regions of the world. Retrieved 16 September 2016.
- International Telecommunications Union – North Korea (country code +850) Communication of 29.IV.2011 – Details of North Korea’s telephone numbering plan as submitted to the ITU. Retrieved 25 November 2016.
- Wikipedia – Telephone numbers in North Korea – Wikipedia entry for telephone number data for North Korea. Includes specific number ranges for each city as well as detail on calling procedures.
- BT – The Phonebook – North Korea (DPRK) – Entry for North Korea in the British Telecom international directory.