Health Minister Łukasz Szumowski said a ban was also being imposed on people leaving their homes except for vital journeys such as heading to work, to a shop or a pharmacy.
The ban, which will be in force until April 11, does not apply to volunteers helping senior citizens. Szumowski said police would be monitoring whether people are abiding by the new restrictions.
On public transport, every other seat on buses or trams will have to remain unoccupied.
Previously, public gatherings of more than 50 people had been banned.
The new restrictions were announced after a meeting of a government crisis management team on Tuesday.
Szumowski appealed to Poles to remain at home and abide by the restrictions, adding that otherwise “we will not be able to save human lives.”
Prime Minister Mateusz Morawiecki warned: "Any breach of these standards, of these restrictions which we are additionally imposing today, can be lethally dangerous."
He added that the new measures were being introduced in order to “buy time” in the fight against the coronavirus epidemic.
Authorities reported on Tuesday that two more patients had died in Poland after contracting the coronavirus, bringing the country’s death toll to 10. A total of 901 people have tested positive for the Covid-19 disease in Poland.
The country has declared a “state of epidemic" and temporarily closed its borders to non-residents in a move to curb the spread of the virus.
The first infection was confirmed by Polish authorities on March 4, while the country's first coronavirus fatality was announced on March 12.
Click on the "Play" button above to listen to an audio report by Radio Poland's Michał Owczarek