More than 140,000 people had fled their homes in recent months before Mount Agung began belching smoke 700m above its summit on Tuesday.
However, so far there have been no changes to flights in the region despite the eruption.
Villagers near the mount were first told to leave in August when it started rumbling but were later allowed to return home. Since then the mount has been rumbling intermittently.
Many of those who returned home have now been ordered to leave and stay overnight in village halls and temples a safe distance from the volcano.
