The sweeping restrictions, agreed by the federal and state governments together and aimed at “limiting social contact in public places” will leave most sites from museums to swimming pools to gyms shuttered.
But supermarkets, banks and post offices will stay open, as will pharmacies and petrol stations.
Hairdressers, construction supply stores and laundromats will also keep operating, said the government, saying that the move was to ensure that “service providers and craftsmen can continue to carry out their trade”.
Strict conditions must apply to ensure that there are no queues and not too many people enter the shops at the same time.
Restaurants and cafes can stay open, but only until 6pm daily.
Hotels will only be used for “essential and explicitly not for tourist purposes”, the government added.
'Stay at home'
It came as German president Frank-Walter Steinmeier urged all citizens to “stay at home”.
“We have to work together to ensure the virus spreads as slowly as possible,” said Steinmeier in a statement.
“So wherever possible: stay at home! Avoid close contact… and have understanding for all restrictive measures.”
Authorities had last week ordered schools shut, and regional trains have been curtailed in a bid to reduce travel.
Chancellor Angela Merkel is set to make an announcement around 6pm Monday.
Bavaria declares disaster, borders shut
The move came after the state of Bavaria declared a 'disaster' situation earlier on Monday and imposed closures on its
Germany also from Monday re-introduced checks on its borders with Austria, France, Switzerland, Luxembourg and Denmark, turning back motorists without an essential reason to enter Germany.
With most of Europe now in lockdown, and stock markets in a tailspin, Berlin on Friday promised companies “unlimited” credit to keep them afloat.
The economic package is worth at least 550 billion euros ($614 billion) initially – the biggest in Germany's post-war history.