General assessment: an extensive but antiquated telecommunications network inherited from the Soviet era; quality has improved; the Bulgaria Telecommunications Company's fixed-line monopoly terminated in 2005 when alternative fixed-line operators were given access to its network; a drop in fixed-line connections in recent years has been more than offset by a sharp increase in mobile-cellular telephone use fostered by multiple service providers; the number of cellular telephone subscriptions now exceeds the population
Domestic: a fairly modern digital cable trunk line now connects switching centers in most of the regions; the others are connected by digital microwave radio relay
International: country code – 359; submarine cable provides connectivity to Ukraine and Russia; a combination submarine cable and land fiber-optic system provides connectivity to Italy, Albania, and North Macedonia; satellite earth stations – 3 (1 Intersputnik in the Atlantic Ocean region, 2 Intelsat in the Atlantic and Indian Ocean regions) (2007).
^ abc"Communications: Bulgaria", World Factbook, U.S. Central Intelligence Agency, 28 January 2014. Retrieved 1 February 2014.
^"Bulgaria Internet Users". www.internetlivestats.com. Retrieved 2017-10-04.
^ abCalculated using penetration rate and population data from "Countries and Areas Ranked by Population: 2012" Archived 2017-03-29 at the Wayback Machine, Population data, International Programs, U.S. Census Bureau, retrieved 26 June 2013
^"Percentage of Individuals using the Internet 2000-2012", International Telecommunication Union (Geneva), June 2013, retrieved 22 June 2013
^"Fixed (wired)-broadband subscriptions per 100 inhabitants 2012", Dynamic Report, ITU ITC EYE, International Telecommunication Union. Retrieved on 29 June 2013.
^"Active mobile-broadband subscriptions per 100 inhabitants 2012", Dynamic Report, ITU ITC EYE, International Telecommunication Union. Retrieved on 29 June 2013.
^Select Formats Archived 2009-05-13 at the Wayback Machine, Country IP Blocks. Accessed on 2 April 2012. Note: Site is said to be updated daily.