Although research has confirmed that the first COVID-19-related lockdown has increased stress and mental health problems in children, less is known about the longer-term effects of the pandemic on children’s COVID-related future anxiety (CRFA). Because of CRFA’s potentially debilitating effects, risk and resilience factors against this anxiety were investigated. To this end, n = 140 children (49% female) in 3^rd and 4^th grade classrooms in Germany were asked to perform a working memory task and to self-report about their CRFA and emotion regulation in December 2020 and in May 2021. More maladaptive emotion regulation in December 2020 contributed to the explanation of a high CRFA score in May 2021, whereas a better performance on working memory updating contributed a lower CRFA score later when controls were in place. These results were confirmed when children’s CRFA in December 2020 was included in the prediction of their later CRFA. They suggest that maladaptive strategies of emotion regulation, such as rumination, may explain higher or increasing levels of CRFA, whereas efficient working memory updating may be an indicator of processing information in a way which shields children from CRFA-related thoughts. The concepts underlying these variables should be included in prevention and intervention efforts.