Failure to cover up the nose and mouth while inside a store – including supermarkets – will be punishable by a fine of up to £100. The rules will not require the use of a medical mask, which ministers want to preserve for frontline health staff.
The announcement brings England in line with Scotland, which made face coverings mandatory in shops on 10 July, and follows the decision to require their use on public transport in England from 15 June.
It comes just days after Boris Johnson was photographed for the first time wearing a mask – bought for £2 from Poundstretcher – to cover his nose and mouth during a visit to a store.
But it will fuel accusations of confusion at the heart of government over the response to coronavirus, after senior cabinet minister Michael Gove insisted on Sunday that coverings would not be made obligatory in English shops.
Labour said the government had been “slow and muddled” over the extension of mandatory use, despite issuing guidance as long ago as 11 May advising people to wear face coverings in enclosed public spaces where they may come into contact with people they would not usually meet.
England has been among the slowest countries in the world to adopt face coverings during the pandemic, with far lower rates of use than in countries like Japan, South Korea and Singapore, where they were ubiquitous almost from the outset, and even behind the US, where they are seen by many as an infringement of freedom.
At least 120 countries have already made them compulsory in public.
According to YouGov polling at the start of this month, just 36 per cent of Britons said they were wearing face coverings while in public places, compared to 90 per cent in Singapore, 83 per cent in Italy, 73 per cent in the US and 65 per cent in Germany.
Mr Hancock will confirm that government guidance is to be updated for all shops, with regulations under the Public Health (Control of Disease) Act 1984 to be passed without the need for a vote in parliament.
While shop staff will be asked to encourage customers to comply, they will not be expected to enforce the rule. This will be a matter for police. Children aged under 11 and people with certain disabilities – such as breathing difficulties – will be exempt, and the fine can be halved to £50 if paid within 14 days.
As early as 21 April, the government’s Scientific Advisory Group for Emergencies (Sage) concluded that “on balance, there is enough evidence to support recommendation of community use of cloth face masks, for short periods in enclosed spaces, where social distancing is not possible”.
The scientists stressed that non-medical coverings were of little use to protect the wearer from infection, but could help avoid an asymptomatic Covid sufferer from passing on the disease to others.
Mr Johnson has faced increasing criticism for shying away from a legal requirement to use them in shops. The Independent Sage group of scientists said that “face masks should be made mandatory in indoors spaces wherever possible”.
But official government messaging has been notably lukewarm about their benefits, with guidance on the reopening of pubs and restaurants stating only that “there are some circumstances when wearing a face covering may be marginally beneficial as a precautionary measure” while “the evidence suggests that wearing a face covering does not protect you”.
The prime minister signalled a shift in policy during a social media broadcast on Friday, in which he said that he was considering “stricter” rules.
But Mr Gove suggested on Sunday that the government was unlikely to take regulatory action, adding: “I don’t think mandatory, no, but I would encourage people to wear face masks when they are inside, in an environment where they might be mixing with others and where the ventilation might not be as good as it might. I think it is basic good manners, courtesy, consideration, to wear a face mask.”
A No 10 spokesperson said: “There is growing evidence that wearing a face covering in an enclosed space helps protect individuals and those around them from coronavirus.
“The prime minister has been clear that people should be wearing face coverings in shops and we will make this mandatory from 24 July.”
Guidance on the use of face coverings in other situations will be kept under review, said Downing Street.
Linda Bauld, professor of public health at the University of Edinburgh, said that “three or four months ago” some of her colleagues in the UK were unsure of the evidence supporting face coverings, but that “now some of those that were quite uncertain some time ago are now definitely saying that new evidence suggests that we should be wearing these”.
Labour’s shadow health secretary, Jonathan Ashworth, said: “The government has been slow and muddled again over face coverings.
“Given the government’s own guidance issued on 11 May advised in favour of face masks, many will ask why yet again have ministers been slow in making a decision in this pandemic, and why it’ll take another 11 days before these new guidelines come into force.
“The health secretary must account for this further delay tomorrow.”
Helen Dickinson, chief executive of the British Retail Consortium, said: “Retailers have made the safety of staff and customers their top priority and we support measures aimed at protecting the health of the public.
“While retailers will play their part in communicating the new rules on face masks, they must not be the ones enforcing these rules. With hundreds of incidents of violence and abuse directed at retail staff every day, we welcome the announcement that enforcement will be left to the authorities, rather than potentially putting hard-working retail colleagues in harm’s way.
"We look forward to further clarity over whether the wearing of face coverings will apply to shop staff. If so, there must be flexibility for colleagues who are in stores all day and can already benefit from other safety measures such as protective screens and 2m distancing.
“Retailers have already spent hundreds of millions installing perspex screens, implementing social distancing measures and providing additional cleaning in stores; we hope this announcement will make shoppers feel even more confident about returning to the high street.”
Claire Walker, co-executive director of the British Chambers of Commerce, said: “Businesses need clarity on the approach to the wearing of face coverings that is consistent and supported by public health evidence. Shops and other indoor businesses need to know what the new rules are as soon as possible.
“Updated guidance, including on enforcement, should be issued swiftly so firms can maintain their Covid-secure status and continue their operations successfully.”