Childhood anxiety is one of the most prevalent mental health issues in Canada (Schwartz, Barican, Yung, Zheng, & Waddell, 2019). In addition to the negative impact it inflicts on children and adolescents, childhood anxiety disorders pose a psychological threat later in life (Vasey & Dadds, 2001). Cognitive behavioural therapy is one of the most effective childhood anxiety treatments (Reynolds, Wilson, Austin, & Hooper, 2012), however is not easily accessible (Thirlwall et al., 2013). One alternative is internet-delivered Cognitive Behavioural Therapy (ICBT) which allows therapeutic services to be provided via the Internet in a more accessible, affordable, and timely manner (Vigerland et al., 2016). Parent-facilitated ICBT provides a low-intensity intervention alternative that delivers online CBT training to parents so that they can implement the therapeutic strategies with their child in their home. However, little is known about the factors affiliated with drop out from parent-facilitated ICBT programs, leaving a deficit in feedback information to modify and improve these treatment programs. This study aimed to investigate parent, child, and program based factors affiliated with withdrawal from a parent-facilitated ICBT program, Anxiety Treatment for Children through Online Education (ACE). Quantitative data obtained from participants who have withdrawn from ACE was analyzed to identify factors associated with dropout. Analyses identified significant differences between completers and non-completers of ACE with respect to program logins, the number of household children with anxiety, and the parental level of education. This study contributes to the aperture in the literature concerning withdrawal from parent-facilitated ICBT programs, whilst providing insight as to common withdrawal factors from these programs.