Mirvis was born in Johannesburg, South Africa, in 1956, the son of Rabbi Dr. Lionel and Freida Mirvis. His father was the Rabbi of the Claremont and the Wynberg Hebrew Congregations in Cape Town. He also served as Rabbi in Benoni for a while and Ephraim attended local schools. Mirvis has written that his father preached against the apartheid system, and visited political prisoners held on Robben Island, while his mother was the principal of the Athlone teacher training college, which was then the county's sole college for training black pre-school teachers. His grandfather, Lazar Mirvis, was a Jewish Minister in Johannesburg.
Mirvis attended Herzlia High School in Cape Town from 1968 to 1973. After moving to Israel in 1973, Mirvis studied at Yeshivat Kerem B'Yavneh from 1973 to 1976 and Yeshivat Har Etzion from 1976 to 1978. He studied at Machon Ariel in Jerusalem from 1978 to 1980 and received his rabbinic ordination there.
At the same time, Mirvis obtained a BA in Education and Classical Hebrew from the University of South Africa and received certification from Yaakov Herzog Teachers College as a high school teacher in Israel.
Mirvis has a deep interest in chazanut and has studied voice and Jewish cantorial music in Jerusalem. He has also been certified as a shochet and mohel. He is a supporter of Tottenham Hotspur Football Club.
In 1982, Mirvis was appointed Rabbi of Dublin's Adelaide Road Synagogue and Chief Rabbi of Ireland in 1985, serving at this post until 1992.
From 1992 to 1996 he was the rabbi of the Western Marble Arch Synagogue in London, after the previous holder of the position, Rabbi Jonathan Sacks, became Chief Rabbi in 1991.
In May 1996, Mirvis was appointed rabbi at the Finchley United Synagogue, also known as Kinloss, in London. Here he founded and directed the community-based, adult education programme, the Kinloss Learning Centre, which has drawn hundreds of participants on a weekly basis since 2003 and has served as an educational model emulated by other communities. Mirvis is the founder rabbi and honorary principal of Morasha Jewish Primary School and founder and President of the Kinloss Community Kollel.
While living in Ireland, Mirvis was Chairman of the Board of Governors of Stratford Jewish Schools, in Dublin, from 1984 to 1992.
Mirvis has been a member of the Steering Committee of the Conference of European Rabbis since 1986. In 1992, he arranged and hosted the Biennial Conference of European Rabbis at the Western Marble Arch Synagogue and in 2001, he led the first group visit by United Synagogue rabbis to the United States.
Mirvis has been the Religious Advisor to the Jewish Marriage Council since 1997. He has served on the Council of the London School of Jewish Studies, on the Steering Committee of the Encounter Conference and the Singer’s Prayer Book Publications Committee.
He has been a member of the Chief Rabbi’s Cabinet since 1996 and was Chairman of the Rabbinical Council of the United Synagogue from 1999 to 2002.
Mirvis served as the President of the Irish Council of Christians and Jews (CCJ) from 1985 to 1992. He has participated in dialogue with Church leaders in the UK at Windsor Castle and Lambeth Palace. In 2005 he addressed a CCJ meeting at the Synod of the Church of England.
Mirvis was the first United Synagogue rabbi to host an address by an imam, Dr. Mohammed Essam El-Din Fahim, in his synagogue. He has also led a delegation of members of his community to the Finchley Mosque and initiated a joint project between his synagogue and the mosque for a Jewish-Muslim public service day on 25 December.
Mirvis was named the successor to Lord Sacks as Chief Rabbi of the United Hebrew Congregations of the Commonwealth on 17 December 2012. Mirvis took office on 1 September 2013.
His appointment was welcomed by the Conference of European Rabbis.
Jeremy Newmark, chief executive of the Jewish Leadership Council in the UK, called the appointment “immensely popular.”
Laura Janner-Klausner, the head rabbi of the Movement for Reform Judaism in Great Britain, said: "I welcome the appointment of Mirvis as another powerful voice for British Jewry. I look forward to working closely with him as a partner on areas of common interests to the Jewish and wider community."
The Orthodox Union in the United States also welcomed Mirvis’s selection as the Chief Rabbi.
As Chief Rabbi of Ireland and before the opening of an Israeli Embassy in Ireland, he represented Israel’s interests at government level and in the media. In 1999, he led a group of British rabbis on a solidarity trip to Israel. Since 1997, he has hosted the annual Bnei Akiva Yom Ha'atzmaut service at Finchley synagogue. Regarding the 2014 Israel–Gaza conflict, while deploring the loss of life in Gaza, Mirvis defended Israel's right to protect itself from Hamas rocket attacks, adding that the conflict was used as a cover to voice anti-Semitic sentiment.
Mirvis was an advocate for the freedom of Soviet Jewry as Chairman of the Irish National Council for Soviet Jewry between 1984 and 1992. In 1986 he lobbied successfully against the request of Nazi war criminal, Pieter Menten, to reside in Ireland. Mirvis has led campaigns to improve the quality of life, safety and security in and around synagogues in the United Kingdom and London particular.
Mirvis has also supported some expanding of women's roles in Orthodox Judaism. In 2012, he appointed Mrs. Lauren Levin as Britain’s first Orthodox female halakhic adviser, at Finchley Synagogue in London. He also supports Shabbat prayer groups for Orthodox women, saying, "Some of our congregations have women prayer groups for Friday night, some Saturday mornings. This is without women reading from the Torah. But for women to come together as a group to pray, this is a good thing." He also supports women becoming United Synagogue trustees, and Orthodox women reciting Kaddish. In 2016, Mirvis launched a new qualifications for female educators to be advisers on Jewish law in the area of family purity and as adult educators in Orthodox synagogues. The part-time training course is 18 months long and is the first such course in the United Kingdom.
Mirvis received the Jerusalem Prize for Education in the Diaspora in 1990, on behalf of the Stratford Jewish Schools, from the President of Israel, Chaim Herzog.
Mirvis married Zimbabwe-born Valerie Kaplan, in Israel. They have four sons, Hillel, Daniel, Noam and Eitan, and nine grandchildren. Their eldest child, Liora Graham, died of cancer in 2011.
Valerie Mirvis was a front line Child Protection Social Worker until May 2012. She is a published author and healthcare specialist.
Mirvis's cousin is bestselling American-Jewish novelist, Tova Mirvis.