Electronic referrals for the programme are provided automatically when a child turns five, officials told reporters.
Appointments for the vaccine can be made via the 989 hotline, the e-Rejestracja website and at vaccination sites, among other options, state news agency PAP reported.
The Pfizer-BioNTech shot may be injected alongside vaccines against other diseases provided the COVID-19 jab is administered to a different part of the body, according to doctors.
The vaccine will be supplied to 5- to 11-year-olds in two age-appropriate doses given 21 days apart.
Children with severe immune disorders will receive a third, additional dose after a further 28 days, public health authorities said.
Source: IAR, PAP