Some 22 people died when the country's most active volcano suddenly erupted last December with tourists on it.
Ten parties now face charges under the Health and Safety at Work Act, which carries a maximum fine of NZ$1.5m ($1.06m; £0.79m).
A further three have been charged as directors or individuals.
These individuals, who have been accused of neglecting health and safety obligations, will face a maximum fine of NZ$300,000.
