How is the national electoral register created?

OSCE/ODIHR, Poland Parliamentary Elections 2019, Needs Assessment Mission Report, 17-20 June 2019, accessed 15 September 2019

“Voter registration is passive. The voter lists are derived from the national electronic population register which is maintained by the Ministry of Internal Affairs and Administration. For each election, voter lists are drawn from this register by local government authorities in co-operation with the NEC. Voters may verify their inclusion in the voter list or obtain information on their voter record by submitting a request to the municipal authority. According to the NEC, there are currently some 30.1 million registered voters.”