The Branch Office of the Warsaw State Archives in Milanówek was established by the Head of the State Archives on April the 21st, 2005. It is located on the second floor of the archival building. Its holdings contain records from the 19th and 20th century. There are mainly modern records - administrative and industrial records of institutions and state-owned companies (both closed down and existing ones which in compliance with the Polish law place their records in the archives after 25 years), court records, records of public prosecutor and correctional service, designing offices, schools, banks and commercial enterprises.