It told shoppers they can claim refunds for items they buy in both brick-and-mortar and online stores if these items are faulty.
Amid the coronavirus pandemic, many Poles have turned to online shopping to avoid contact with people.
When shopping online "you have the right to complain on the same terms as for purchases made in the stationary store," the Office of Competition and Consumer Protection (UOKiK) said on its website.
It added: "If the product is found to be defective within two years from the date of delivery, contact the seller as soon as possible. You can demand the product to be repaired, replaced, sold at a lower price, and if the defect is significant, you can claim your money back."
A customer may also "return a product purchased online without stating a reason within 14 days of its receipt," the Polish consumer watchdog noted.
Black Friday and Cyber Monday are when both regular and online stores offer special deals to shoppers. The tradition originated in the United States but is increasingly popular in Poland as well.
The two days are widely seen as the beginning of the Christmas shopping season.
Black Friday follows Thanksgiving Day in the United States and this year falls on November 27.
Meanwhile, Cyber Monday is the Monday following Thanksgiving and sees major discounts offered by online retailers.
"This year Black Friday will lack the momentum of previous years, as most of the stores in the shopping malls will still be closed due to restrictions related to COVID-19," the Polish consumer watchdog said.
Tougher measures to battle COVID-19 came into effect across Poland earlier this month following a surge in cases amid a second wave of the pandemic.
Shopping malls have been ordered to limit their operations, though some retail outlets, such as grocery stores, pharmacies and drugstores, are allowed to stay open to customers.
Source: IAR, uokik.gov.pl
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