The plastic bag levy rises from 15c to 22c today.
It is estimated that the use of disposable plastic bags has been reduced by almost 90% since the introduction of the levy in March 2002.
In 2002, the Government estimated that 1.2bn plastic bags were given out free every year.
The scheme, which has been hailed a success by the Department of the Environment, was introduced to combat litter and reduce environmental damage caused by plastic bags, which are used for minutes but last for hundreds of years.
