Egan was born in Queens, New York, United States. In 1970, as a sculpture major, he earned a Bachelor of Fine Arts degree at Georgetown University in Washington, D.C. as one of Georgetown’s first art majors. Egan started his career in the arts, concentrating on printmaking and painting, and the music business. As early as 1969, Egan was playing guitar and composing songs with surf-rock group the Malibooz. While an undergraduate, he was a lead guitarist and backup vocalist for the college-formed group Sageworth and Drums, also known as Sageworth. The group evolved from a group of Georgetown University undergraduate students playing weekend mixers and parties to a tight, professional headlining act with a reputation as one of the best and most original bands in the greater Washington, D.C. area. Other members included Peter Barry Chowka, lead vocal and guitar; John Zambetti, guitar and backing vocals; Tom Guidera, bass and backing vocals; and Matthew Sheppard, drums, with Annie McLoone added later as a lead singer.

In late 1971, Sageworth relocated to Boston and spent the next two years performing around the Northeast before finally breaking up, at which point Walter moved to Los Angeles and began his career as a solo artist.

In 1977, Lindsey Buckingham of Fleetwood Mac co-produced Walter Egan’s first album, Fundamental Roll, with Stevie Nicks, also of Fleetwood Mac. The hit song, “Magnet and Steel”, inspired by Nicks and from his second album Not Shy, was featured in the 1997 film Boogie Nights, the 1998 film Overnight Delivery, and the 1999 film Deuce Bigalow: Male Gigolo. Egan also wrote “Hearts on Fire”, which was covered by Gram Parsons on his album Grievous Angel, and “Hot Summer Nights”, which was the first hit for the band Night, and included such session musicians as Nicky Hopkins and Robbie McIntosh. Egan scored minor hits with his original version of “Hot Summer Nights” (#56 Can.), as well as “Only the Lucky” and “Fool Moon Fire”.

In 1985, Egan was a four-time champion on the game show Catchphrase. In 1986, Egan appeared as a contestant on the television game show Scrabble. During his introduction segment, Egan identified himself as a singer and songwriter. Host Chuck Woolery asked Egan to sing a bit from one of his songs, and he sang the main hook from “Magnet and Steel”.

In 2008, he participated in a music industry seminar (with Bill Danoff) at Georgetown University.

In 2011, from his home in Franklin, he produced a new album entitled Raw Elegant that was released on Spectra Records.