Coun James Hull, a Labour councillor who represents the St George’s ward in Preston, was rapped by magistrates after blowing a positive breath test.
Hull, of Brockholes View, Preston, confirmed the conviction when he was contacted by the Evening Post.
The 54-year-old said: “ I was only slightly over the limit.
“If it had been any lower I probably would not have been charged.”
The councillor was stopped on London Road in Walton-le-Dale on December 19 last year driving his Mazda MX5.
When police performed a breath test he had 41 mg of alcohol in his breath - the legal limit being 35mg.
Hull had previously denied the offence, but later appeared at Preston Magistrates’ Court where he pleaded guilty to driving while over the legal limit.
He was ordered to pay a £390 fine, a £39 victim surcharge and prosecution costs of £250 at a rate of £100 a month.
The bench ruled his period of disqualification would be reduced by 14 weeks if he completes a drink drive rehabilitation course.
A spokesman for Preston City Council said: “There is no impact in so far as his position as a councillor is concerned.”
He was caught during the season of Lancashire Police’s Christmas drink driving campaign.
In December 2014 a total of 5,012 drink drive tests were carried out across the county with 153 people failing the test.