People across England will be required by law from Monday to self-isolate if they test positive for the coronavirus or face a 1,000-pound fine, which increases to 10,000 pounds for repeat offenders.
The government said that as the infection is now spreading rapidly again across the country, the tougher measures are aimed at ensuring compliance and reducing the spread of COVID-19.
"These new measures are about saving lives. Everyone must take personal responsibility and self-isolate if they test positive or if told to do so by NHS Test and Trace," said UK Home Secretary Priti Patel.
"For those who fail to do so, the police will enforce the law. These new fines are a clear sign that we will not allow those who break the rules to reverse the hard-won progress made by the law-abiding majority," she said.
Fines for a breach of self-isolation legal requirements start at 1,000 pounds, in line with the existing penalty for breaking quarantine after international travel.
This could increase to up to 10,000 pounds for repeat offences and the most serious breaches, including for those preventing others from self-isolating.
The rules come in as infections continue to rise across the UK but only 18 per cent of people with symptoms of the deadly virus going into isolation, according to a study commissioned by the UK government.
"As cases rise it is imperative we take action, and we are introducing a legal duty to self-isolate when told to do so, with fines for breaches and a new 500 pounds support payment for those on lower incomes who can't work from home while they are self-isolating," said UK Health Secretary Matt Hancock.
"These simple steps can make a huge difference," he said.