He was charged with drink-driving after allegedly being involved in a collision in Richmond, west London, on March 18th and pleaded guilty earlier today.
Drink driving laws, and legal alcohol limits, have been in place for a number of years - longer than you might think.
Prosecutor Katie Sinnett-Jones told Wimbledon Magistrates' Court on Monday that the incident happened at around 3.50pm when McPartlin drove his Mini around a "sharp bend and lost control" then ended up on the wrong side of the road.
3pm: TV presenter Ant McPartlin has been given a 20-month driving ban and fined £86,000 after pleading guilty at Wimbledon Magistrates' Court to drink driving. The legal limit is 35 microgrammes per 100 millilitres of breath.
The court heard that the driver of the other Mini said afterwards he thought he and his family were going to die in the collision.
In a statement read in court by Ms Sinnett-Jones, the driver said: "Myself and my family were in deep shock as we believed we could have died as as a result of Mr McPartlin's reckless driving".
"Anthony McPartlin is sorry and is doing everything he can to ensure this never happens again", Mr Walker said.
McPartlin was also told to pay £255 in costs.
Double the limit Ant appears dazed after the crash last month
Fining him, she said: "Because of the seriousness of this offence, the financial pain must be imposed on you as on any other offender".
The court heard Ant's mother, Christine Woodhall, was in the vehicle with him at the time.
Dec fronted the final two episodes solo, including the finale which was filmed at Universal Orlando Resort.
His publicist said last month: "Ant has made a decision to go back into treatment and step down from his current TV commitments".
The Ant and Dec star has since pulled out of his upcoming TV commitments and asked for time off for the "foreseeable future".
Since his arrest and charge, Ant stepped down from his hosting duties on Saturday Night Takeaway and Britain's Got Talent, with his right-hand man and friend Declan Donnelly taking the reins.
ITV said the show, in which the judges and presenters were wowed by a magician, was the most-watched programme of the night.
ITV said Saturday's Britain's Got Talent instalment was the most-watched entertainment show of the year so far and that it was the most popular programme on any channel so far this year for 16 to 34-year-olds.