Verreau was born near Quebec City, Montreal, and studied music at Laval University in Quebec, and in Paris. He made his debut in the early 1950s at the Op_ra de Lyon, and went on to Rome to study bel canto with Beniamino Gigli.

In 1956, he joined the New York City Opera. He made his Royal Opera House debut in 1957; he made his Metropolitan Opera debut in 1963 in Faust.

He sang frequently with the Montreal Symphony Orchestra, and performed with the Quebec Opera, the Opera Guild of Montreal, the Canadian Opera Company of Toronto, and at many Canadian festivals, including Expo '67, which was held in Montreal. He also appeared on CBC Radio and Television.

The people's-choice award at the Montreal International Music Competition was named after Verreau in 1999.