Summadayze was an annual Australian music festival held in the month of January.

The first event occurred on 1 January 1999 at the Sidney Myer Music Bowl in Melbourne.

[1] Summadayze was held at Doug Jennings Park on the Gold Coast in 2003.

In 2004, the Summadayze festival was held in Melbourne, Gold Coast, Auckland and Perth.

[3] In 2011, events were again held in Melbourne, Adelaide, Gold Coast and Perth.