McGegan received his early education at Nottingham High School. He subsequently studied music at Corpus Christi College, Cambridge and at Magdalen College, Oxford. McGegan has participated in some of the earliest "authentic-performance" recordings during the 1970s as a baroque flautist, including Christopher Hogwood's seminal recordings of Mozart symphonies. He has taught music at such UK institutions as King's College, Cambridge, Oriel College, Oxford, and the Royal College of Music. From 1993 to 1998, he was Principal Guest Conductor of the Scottish Opera in Glasgow.
In the USA, McGegan has served as artist-in-residence at Washington University in St. Louis, beginning in 1979, when he was initially scheduled for one semester in residence, but his residency continued until 1985. Following his time at Washington University, McGegan first guest-conducted the St. Louis Symphony in 1986, and has since returned continuously as a guest conductor. In 1985, McGegan became music director of the Philharmonia Baroque Orchestra in San Francisco and Berkeley, California. In 1988, he served as Music Director of the Ojai Music Festival alongside Peter Maxwell Davies and Diane Wittry. Since 2013, he has been Principal Guest Conductor of the Pasadena Symphony. In October 2018, the Philharmonia Baroque Orchestra announced that McGegan is to stand down as its music director after the 2019-2020 season, and to take the title of music director laureate.
From 1991 to 2011, McGegan was Artistic Director of the Göttingen International Handel Festival. He was music director of the Irish Chamber Orchestra from 2002 to 2005. In 2014, he became Artist in Association with Australia’s Adelaide Symphony. He has also held long-term appointments ith the Drottningholm Theatre, where he served as principal conductor from 1993 to 1996, the Milwaukee Symphony Orchestra, and the Saint Paul Chamber Orchestra. McGegan also founded the chamber music group, The Arcadian Academy.
McGegan has made more than 100 recordings, including many with Philharmonia Baroque and singers such as Lorraine Hunt Lieberson and Lisa Saffer, for such labels as Philharmonia Baroque Productions and harmonia mundi. He was nominated for a Grammy Award for his 2011 release on the orchestra's label of the Symphonies nos. 88, 101, and 104 of Joseph Haydn.
McGegan resides in Berkeley, California and Glasgow. He has collected a number of honors, including: an honorary degree from the Royal College of Music in London; the Handel Music Prize from the Handel Festival in Halle, Germany; the honorary medal of the Friends of the Drottningholm Theatre; the Order of Merit of the State of Lower Saxony (Germany); the Medal of Honor of the City of Göttingen, and a declaration of Nicholas McGegan Day, by the Mayor of San Francisco in recognition of his work with Philharmonia Baroque. He was appointed Officer of the Order of the British Empire (OBE) in the 2010 Birthday Honours.
- St. Louis Symphony Orchestra, pre-concert talk by Nicholas McGegan and Amy Kaiser, January 31, 2015.
- Andrew Clements (1 August 2005). "Baroque star". The Guardian. Retrieved 2009-10-18.
- Jason Victor Serinus (2015-09-29). "Nicholas McGegan: 30 Years and Counting with Philharmonia Baroque". San Francisco Classical Voice. Retrieved 2018-10-02.
- Sarah Bryan Miller (2016-10-01). "Conductor Nicholas McGegan brings all-Mozart program to SLSO". Saint Louis Post-Dispatch. Retrieved 2018-10-02.
- Corinna da Fonseca-Wollheim (2014-08-05). "Like a Jazz Band, but 18th Century". The New York Times. Retrieved 2018-10-02.
- Michael Cooper (2018-10-02). "Maestro of the Influential Philharmonia Baroque Orchestra to Step Down". The New York Times. Retrieved 2018-10-02.
- Michael Schäfer (30 December 2010). "Händel-Festspiele: Ära McGegan geht zu Ende". Göttinger Tageblatt. Retrieved 2011-06-12.
- Ilona Wallace (2014-09-16). "Adelaide Symphony Orchestra 2015 program released". The Adelaide Review. Retrieved 2018-10-02.
- James R Oestreich (2012-10-26). "Brahms: Serenades". The New York Times. Retrieved 2018-10-02.
- "No. 59446". The London Gazette (Supplement). 12 June 2010. p. 24.
- Official Nicholas McGegan website
- harmonia mundi page on Nicholas McGegan
- Philharmonia Baroque Orchestra web site
- Interview with Nicholas McGegan, 19 July 1988
- Rayfield Allied Biography
| Music Director, Philharmonia Baroque Orchestra
John Eliot Gardiner
| Artistic Director, Göttingen International Handel Festival
| Music Director, Irish Chamber Orchestra
Anthony Marwood (Artistic Director)