The couple, who met while filming the 2006 hit Disney TV movie "High School Musical," reportedly split for no real reason other than their relationship just "ran its course," according to a report from E! Online's Marc Malkin & Ken Baker.
Sources told the writers that there was "no third party involved" and that they are going to remain friends.
Next up for the former couple? Vanessa stars in Sucker Punch (2011) - Zack Snyder's violent spin on Alice in Wonderland; and Zac is currently filming his next project, The Lucky One - about an Iraq war veteran (not to be confused with the very similarly titled 2008 Tim Robbins/Rachel McAdams film about about Iraq war veterans) - which is due in 2012.
The news comes just a day before Vanessa's 22nd birthday.