An Australian has been sent to jail for a year for sharing a marijuana joint on a Bali beach.

Nicholas Langan, of Townsville, was initially charged with drug possession, which carries a maximum 12 years' jail.

Prosecutors then asked the court to sentence the 25-year-old painter to a maximum four years for drug users.

The time Langan has spent in Kerobokan jail since his January 26 arrest will count towards his sentence.

During the trial, he gave a long apology for his actions, saying he had a history of marijuana addiction that he was trying to overcome.

Chief Judge Cening Budiana on Thursday acknowledged Langan had been "polite and frank" with the court.

Also sentenced to one year in jail was Hanung Pekik Hermantoro, 25, a driver for The Green Room Villas, who shared the joint with Langan.

Police say they arrested the pair on a Canggu beach after midnight on January 27, after a tip-off from a security guard.