The COVID-19 pandemic has profoundly affected children's care and education worldwide. This article reports on patterns of participation in early childhood education and care (ECEC) across Australia as influenced by the COVID-19 pandemic and national policies. Using ECEC data from Xplor -- a software platform used across Australian childcare centres (2019: n = 229,349; 2020: n = 229,468), patterns of attendance rates were examined nationally in 2019 and 2020 by service-level and family-level characteristics. The average attended hours per week of ECEC nationally in 2020 (18.32 hours) was less than that in 2019 (21.26 hours). Attendance rates at ECEC in 2020 declined rapidly from 66% to 26.2% at the onset of the COVID-19 outbreak. Fee-free subsidy from Australian governments did not substantially increase attendance or reduce disparities in attendance for vulnerable families. Low ECEC attendance rates for prolonged periods could have significant implications for child development, particularly for children from vulnerable backgrounds.