Drivers are being warned that they are more than twice as likely to have a breath test in December than in any other month.
In December last year, police arrested 48,804 drivers on suspicion of drunk driving.
The average for the remaining 11 months in England and Wales was 23,043.
A total of 5,210 drivers tested positive (or declined) last December – a failure rate of 11%.
But analysis of Home Office data by AlcoSense Breathalysers shows huge differences across the country.
In North Wales, 3,964 drivers were tested last December, compared to 31 in Wiltshire.
There were also large differences in the percentage of drivers who failed the breath test.
In Northamptonshire, the county with the highest number of tests in England (2,957), the failure rate was only 2%. While in Cambridgeshire, where 1,070 tests were conducted, a disturbing 30% exceeded the limit.
“We may be going to Christmas parties less this year, but several studies show that people drank more alcohol during lockdown,” said Hunter Abbott, MD of AlcoSense Laboratories.
“The increase is caused by job insecurity and pandemic fear, fueled by the increase in drinking at home where the measures are more generous than in a cafe or restaurant.
“This trend makes it more likely that people will get behind the wheel the next morning and drive with alcohol in their system. Even a small amount of alcohol slows down reaction time, slows down judgment and decreases concentration, increasing the risk of accidents.
“One in five drink-driving convictions is in the morning, but using a personal breathalyzer takes the guesswork out of knowing when the alcohol disappeared the morning after the night before.”
The police forces that conducted a large number of tests last December were also Hampshire (2,856), Thames Valley (2,050), Lancashire (1,770) and Greater Manchester (1,728).
The Greater London Metropolitan Police area topped the list of positive breath tests, with 412 drivers going over the limit last December.
Nationally, 8,860 people were injured last year because a driver exceeded the limit, including 240 deaths.