This means that non-essential shops and business have been ordered to close by the government.
The Prime Minister announced the third national lockdown in a televised address on Monday night.
However essential stores such as supermarkets are allowed to remain open.
In the previous lockdowns, shops changed opening hours and introduced a number of safety measures as well as new rules and restrictions.
But will this be the same for the third lockdown?
We have pulled together a list of the opening times, rules and restrictions in place at the major supermarkets in Portsmouth over the coming weeks.
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1. Supermarket lockdown rules
Tesco is asking that only one person per household enter the store, face masks are also required by law. Tesco also has a priority shopping hour every Wednesday and Sunday between 9am-10am for our more vulnerable and elderly customers. NHS, emergency service and care workers now have priority access at any time. Picture: Hollie Adams/ Getty Images Photo: Hollie Adams/Getty Images
2. Waitrose
Waitrose is open as usual including 8am to 8pm Mon-Sat. Click and collect services are available. There is a purchase limit on a small number of items. Masks and social distancing rules. Customers are asked to only send one person per household to a store at a time. Waitrose also says that it will prioritise disabled, elderly and vulnerable customers whenever there’s a queue outside. Photo: Chris Moorhouse
3. Asda
Asda in Fratton is open 7am to 11pm on weekdays. Asda are limiting customers allowed in stores, customers are also asked for maintain social distancing and pay contactlessly where possible. Masks are required. Scan and go is now available at all supermarkets, superstores and supercentres. Photo: Google Maps
4. Sainsbury's
Sainsbury’s is open in Portsmouth with normal hours. Shoppers should follow social distancing and wear masks in store. Elderly and vulnerable customers and NHS and care workers with an NHS ID are being offered priority access. The supermarket also asks that where possible you only send one adult per household. Photo: WikiMedia Commons / Editor5807 (labelled for reuse)