North Yorkshire Police says a "shocking" number of fines have been handed out to people moving from tier three to tier two areas to drink in the city’s pubs and bars.
The force said more than 160 fines were handed out in tier-two York over the weekend, most went to people living in tier three areas, which includes the whole of neighbouring South and West Yorkshire.
The force has said it will continue to patrol the city for anyone drinking illegally.
Officers visited pubs in the city from Friday and found large numbers in breach of the regulations.
Some of the drinkers dispersed and left when spoken to by officers but action was taken against others who stayed, the force said.
Supt Mike Walker, head of the North Yorkshire Police response to Covid-19, said the "vast majority" of fines went to people from tier three who visited the tier two city to mix and socialise indoors in breach of regulations.
He said: "Where we encounter people who refuse to adhere to the regulations and believe their pint is more important than someone's life, we will use our enforcement powers
"If you choose to visit the city of York from tier three areas without a justifiable reason... chances are you will encounter one of our officers and you'll be asked about the reason for your visit."
Councillor Denise Craghill said: "No-one in the city wants to put loved ones at risk for the sake of a night out and undo the city's hard work and sacrifice."
Last month, the same force introduced Covid border patrols to stop people from Doncaster travelling to York.
Police are carrying out checks on roads leading into the county and in York – including the A19 bewteen Doncaster and York – to stop Covid-19 rule breakers while people arriving in York by train could also be stopped by officers and asked where they have travelled from in a bid to prevent the spread of coronavirus.