"With open arms and with an infinite energy, Berliners welcomed thousands of refugees to Berlin," the city state's parliament said.
"Without the unconditional help of thousands of Berliners in the refugee shelters, and the donations of clothes, toys, medicine and food... Berlin would not have been able to cope with this exceptional situation," it added.
The institutions which would offer free entry for the day would be listed on a website called "Berlin says thanks" or berlin-sagt-danke.de.
Further details of the programme were not yet available.
The decision came as the capital's authorities were under fire for allowing chaos to reign in overwhelmed refugee offices and shelters.
Families sleeping outside in sub-zero temperatures and brawls in overcrowded dormitories have cast a harsh spotlight on Berlin, which likes to bill itself as a hip European city that is "poor but sexy".
"Capital of failure" was the withering assessment by news site Spiegel Online of how the chronically broke city-state of 3.5 million has dealt with some 70,000 refugee arrivals this year, compared to other German states, including Bavaria, which have taken in far more asylum seekers.
The head of Berlin's main asylum seeker registration centre, Franz Allert, was forced to resign late on Wednesday over the chaos plaguing the office, which is struggling to process a record number of newcomers.