Restrictions will be imposed on shopping malls there, while hotels, theatres, cinemas, museums and swimming pools in the region will have to shut for at least a week.
In the rest of the country, other, mostly less-severe curbs designed to limit the spread the virus will remain in place until at least March 28.
Health Minister Adam Niedzielski told reporters on Friday that the average number of fresh daily infections in Poland had risen by a third week on week.
“Those numbers make an impression,” he said.
Pomerania is among the regions in Poland with the highest number of new coronavirus cases.
New hospital ward for coronavirus patients in the northwestern Polish city of Szczecin. Photo: PAP/Marcin Bielecki
In another regional lockdown, a range of restrictions on public life were reintroduced in the northeastern Warmia and Mazuria province at the end of last week.
Poland on Friday reported 15,829 new coronavirus infections across the country and 263 more deaths, bringing its total number of cases during the pandemic to 1,766,490 and fatalities to 44,912.
Following a period in which restrictions were eased around the country, the Polish authorities have adopted a strategy of bringing back regional curbs in areas most hit by the virus amid a fresh surge in the epidemic.