Her release was originally expected Saturday morning but was delayed because a jail official, who has the only key to the women’s prison, slept in.
Leslie was sentenced by a Bali court on Friday to three months in jail for possessing two tablets of ecstasy, a period of custody she has already served.
Leslie, who arrived at the court handcuffed but smiling, look composed as the verdict and sentence were handed down.
She sat quietly with her hands clasped on her lap as her interpreter translated the words of the presiding judge.
The outcome of the trial follows exactly a demand by Indonesian prosecutors who recently dropped earlier demands for a tough sentence of up to 15 years.
They had said it had been proven that Leslie had been a drug user and not a trafficker, which is a far more serious offence.
The 24-year-old Adelaide-born woman was arrested on August 20 outside a Bali dance party carrying two ecstasy pills.
Before the verdict her Australian lawyer, Ross Hill, said his client should never have been arrested or charged and that it had been a "scandal" that the case had gone to court.
He said Leslie's three months behind bars completed at midnight on Friday Bali time.