220 Background: Personal costs of childhood cancer can contribute to disparities in health outcomes. The purpose of ACCL20N1CD is to examine trajectories of parental costs and the associated financial distress, cost coping behaviors, and household material hardships (HMH) during treatment for pediatric ALL. Objective is to report baseline characteristics of the parents and their households. Methods: The study used a prospective cohort design with repeated measures. Setting was Children’s Oncology Group (COG) practices at National Cancer Institute Community Oncology Research Program (NCORP) institutions. Parents who use English or Spanish, and have children newly diagnosed with ALL treated at COG NCORP practices were eligible. Parents were asked to complete surveys at 3 time points, including baseline (T1; during induction and <7 days after planned induction remission evaluation). Surveys included items about (a) parent socio‐economic status, financial distress measured by 8-item Personal Wellness Scale (PFWS), and cost coping behaviors, and (b) HMH. Factors related to high PFWS scores were evaluated by logistic regression. Results: Of 104 evaluable parents, most were female (83.7%), white (65.4%), non-Hispanic (48.1%), partnered (79.8%), > high school diploma (93.3%), used English (84.6%), worked full (48.1%) or part (5.8%) time, and paid for their child’s care with public insurance (57.7%). Median household income=$50,000 (Inter-Quartile Range/IQR 20,000-100,000) for 4 (IQR 4-5) people. Not including wages lost due to caregiving, out of pocket payments for medical care + other ALL-related costs in the prior month >15% of monthly income for 51.9% of households, which is considered financially catastrophic. 24.0% of households lacked food stability; 21% had housing insecurity. Conclusions: At baseline, sizeable proportions of parents exhibit high out of pocket costs, high financial distress level, and multiple cost coping behaviors with implications for future health and individual and household quality of life.