A landline ( land line, land-line, main line, fixed-line, and wireline) is a telephone connection that uses wire from the owner's premises also referred to as: POTS, Twisted pair, telephone line or public switched telephone network (PSTN).
Landline services are traditionally provided via an analogue copper wire to a telephone exchange. Landline service is usually distinguished from other more modern forms of telephone services which use Internet Protocol based services over optical fiber (FTTX) or other broadband services (VDSL/Cable) using Voice over IP, although sometimes modern fixed phone services delivered over a fixed internet connection are sometimes referred to as a landline (non-cellular service).
A subscriber's telephone connected to a landline can be wire or cordless and typically refers to the operation of wireless devices or systems in fixed locations such as homes. Fixed wireless devices usually derive their electrical power from the utility mains electricity, unlike mobile wireless or portable wireless, which tend to be . Although mobile and portable systems can be used in fixed locations, efficiency and bandwidth are compromised compared with fixed systems. Mobile or portable, battery-powered wireless systems can be used as emergency backups for fixed systems in case of a power blackout or natural disaster.
Other aspects of landline is the ability to carry high-speed internet popularly known as Digital subscriber line (DSL) which links back to the digital subscriber line access multiplexer (DSLAM) within the central office, T-carrier, or ISDN.
The 2013 statistics show that the total number of fixed-telephone subscribers in the world was about 1.26 billion. The number of landline subscribers continuously decreases due to upgrades in digital technology and the conveniences that come with switching to wireless, internet, optical fiber, or computer network-based alternatives. there were about 1.26 billion fixed-telephone subscribers in the world, but this number has been dwindling due to the rise of mobile networks and the obsolescence of old copper wire networking.
In many parts of the world, including Africa and India, the growth in mobile phone usage has outpaced that of landlines. In the United States, while 45.9 percent of households still had landlines as of 2017, more than half had only mobile phones. This trend is similar in Canada, where more than one in five households used mobile phones as their only source for telephone service in 2013. However, voice over IP (VoIP) services offer an alternative to traditional landlines, allowing numbers to remain in use without being tied to a physical location, making them more adaptable to modern ways of working.
In the early 21st century, installations of landline telephones has declined due to the advancement of mobile network technology and the obsolescence of copper wire networking. It is more difficult to install landline to every user than it is to install transmission towers for mobile service that many people can connect to. Some predict that these metallic networks will be deemed completely out of date and replaced by more efficient broadband and fiber optic landline connections extending to and places where telecommunication was much more sparse. In 2009, The Economist wrote "At current rates the last landline in America will be disconnected sometime in 2025."
In 2004, only about 45% of people in the United States between the ages of 12 and 17 owned cell phones. At that time, most had to rely on landline telephones. Just 4 years later, that percentage climbed to about 71%. That same year, 2008, about 77% of adults owned a mobile phone.
In Canada, more than one in five of households use cell phones as their only source for telephone service. In 2013, statistics showed that 21% of households claimed to only use cellular phones. Households that are owned by members under the age of 35 have a considerably higher percentage of exclusive cell phone use. In 2013, 60% of young household owners claimed to only use cell phones. In 2019, 54% of Canadian households Landline and cellular telephone use by province, 2019 by Statistics Canada. Retrieved 27 July 2023. and 80% of French households Share of private households owning a landline phone in Germany from 1998 to 2022 by statista. Retrieved 27 July 2023. had a landline telephone.
Estonia and the Netherlands have retired the legacy parts of the public switched telephone network (PSTN). In the United Kingdom, the analogue copper landline network is due to be terminated in 2025. The VoIP replacement is known as "Digital Voice" (on a BT service) in the UK. France, Germany and Japan are also in the process of replacing theirs.
By means of porting, voice over IP services can host landline numbers previously hosted on traditional fixed telephone networks. VoIP services can be used anywhere an internet connection is available on many devices including Smartphones, giving great flexibility to where calls may be answered and thus facilitating remote, mobile and home working, for example. VoIP porting allows landline numbers to remain in use, whilst freeing them from actual landlines tied to one location. This is useful where landline numbers are believed to be preferred by callers, or where it is preferable that legacy landline numbers remain connected.