Belfrage was born in Los Angeles in 1940, the son of British/American socialist writer Cedric Belfrage and his wife Molly Castle. He grew up in New York and London, and studied French and Italian at University College London, He became a Master of Wine in 1980.
Belfrage has contributed to publications such as Decanter, The World of Fine Wine, Wein Gourmet, and shared a column in Harpers Magazine with Franco Ziliani, with whom he has also collaborated on contributions to Tom Stevenson's annual Wine Report. For several years he has contributed the Italy section to Hugh Johnson's Pocket Wine Book as well as to the Oz Clarke Pocket Wine Book.
- Life Beyond Lambrusco (1985)
- Barolo to Valpolicella: The Wines of Northern Italy (1999)
- Brunello to Zibibbo: The Wines of Tuscany, Central and Southern Italy (2001)
- The Finest Wines of Tuscany and Central Italy (2009)
- Nicolas Belfrage profile winepros.com.au