Samaritans is a registered charity aimed at providing emotional support to anyone in emotional distress, struggling to cope or at risk of suicide throughout the United Kingdom and Ireland, often through its telephone helpline. Its name derives from the biblical parable of the Good Samaritan, although the organisation itself is not religious.

Its international network exists under the name Befrienders Worldwide, which is part of the Volunteer Emotional Support Helplines (VESH) with Lifeline International and the International Federation of Telephone Emergency Services (IFOTES).

Samaritans was founded in 1953 by the Rev. Chad Varah, a Church of England vicar in the Diocese of London. His inspiration came from an experience he had had some years earlier as a young curate in the Diocese of Lincoln. He had taken a funeral for a fourteen-year old girl who had died by suicide because she believed she had contracted an STI, when in reality she was menstruating. Varah placed an advertisement in a newspaper encouraging people to volunteer at his church, listening to people contemplating suicide.

The movement grew rapidly: within ten years there were 40 branches and now there are 201 branches across Great Britain and Ireland, deliberately organised without regard to national boundaries on the basis that a service which is not political or religious should not recognise political or sectarian divisions. Samaritans offers support through over 21,200 trained volunteers (2015) and is entirely dependent on voluntary support. The name was not originally chosen by Chad Varah: it was part of a headline to an article in the Daily Mirror newspaper on 7 December 1953 about Varah's work.

In 1972, BBC1 ran an 11-episode television series called The Befrienders, featuring fictional stories about people in desperate situations who reach out to the Samaritans. Although it was cancelled after one season, the series helped to raise public awareness about their work, leading to a significant increase in inbound calls, as well as a surge in the number of volunteers in the UK.

In 2004, Samaritans announced that volunteer numbers had reached a thirty-year low, and launched a campaign to recruit more young people (specifically targeted at ages 18–24) to become volunteers. The campaign was fronted by Phil Selway, drummer with the band Radiohead, himself a Samaritans volunteer.

In 2004, Chad Varah announced that he had become disillusioned with Samaritans. He said, "It's no longer what I founded. I founded an organisation to offer help to suicidal or equally desperate people. The last elected chairman re-branded the organisation. It was no longer to be an emergency service, it was to be emotional support". One in five calls to Samaritans is from someone with suicidal feelings. Samaritans' vision is that fewer people will die by suicide.

In 2005, a rapprochement was reached when Varah met with the new chief executive, and then chairman, of The Samaritans and enjoyed hearing about the continued essential and enlightened work Varah had begun in 1953. In 2006, Varah's eldest son, Michael Varah, was appointed to sit on the newly created board of trustees.