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.
MORE NEWS: McDonald's confirms which Portsmouth restaurants will be closed to customers in third lockdown | Full list of Gunwharf Quays stores and restaurants still open in Portsmouth during third lockdown
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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However essential stores such as supermarkets are allowed to remain open.