New research found 19% of packs examined in Newbridge were counterfeit, compared with 14% in Naas and 16% in Leixlip.
More than half of cigarette packs surveyed in Newbridge and Naas did not have Irish tax paid on them, according to new research commissioned by tobacco company JTI Ireland.
The 2026 Empty Pack Survey examined discarded cigarette packs collected from streets and public bins in 22 towns and cities across the country.
In Newbridge, 53 per cent of packs surveyed were classified as non-Irish duty paid (NIDP), with 19 per cent identified as counterfeit cigarettes.
In Naas, 51 per cent of packs had no Irish duty paid, including 14 per cent which were counterfeit.
The figure was slightly lower in Leixlip, where 48 per cent of packs surveyed were non-Irish duty paid and 16 per cent were identified as counterfeit.
Non-Irish duty paid cigarettes include both illegal tobacco products and legally purchased cigarettes brought into Ireland from abroad on which Irish tax has not been paid.
Nationally, the survey found 57 per cent of the cigarette packs examined were non-Irish duty paid, while 14 per cent were counterfeit.
Galway recorded the highest level of non-Irish duty paid packs at 75 per cent, followed by Swords at 66 per cent.
Wexford had the highest proportion of counterfeit cigarettes at 25 per cent, followed by Ennis at 20 per cent and Waterford at 19 per cent.
The survey was carried out on behalf of JTI Ireland, which manufactures tobacco brands including Benson & Hedges, Silk Cut and Mayfair.
A total of 5,000 discarded cigarette packs were collected between February 16th and April 3rd and examined for their origin, tax markings and authenticity.
JTI Ireland says Government figures show €758 million in tax revenue was lost to illegal tobacco products last year.
The company is calling for stronger enforcement against cigarette smuggling and counterfeiting, as well as what it describes as a more moderate approach to increases in tobacco excise.

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