The government says the new tax will cost the government €1.3 billion ($1.8 billion) annually, but analysts say the real figure could be higher.
The government estimates the cost will be €1,500 ($1,750) a year for an individual, and €600 ($700) for a family of three.
In contrast, the Tobacco Free Ireland campaign has estimated that the tax will result in a tax cut of €3,400 ($4,300) a person per year, or €50 ($55) a family per year.
The average Irish household, which is estimated to have around 5,000 tobacco smokers, is expected to save €5 ($6) a week on cigarettes.
According to a 2015 study by the Institute for Economics and Peace, a tobacco company, the average family saves €2 ($3) a day on cigarettes in Ireland.