Abstract Objectives To examine Healthy Eating Index (HEI)-2015 scores for dietary intake on weekends versus weekdays overall and by the race/ethnicity of mothers and their children from households eligible for Supplemental Nutrition Education Program-Education (SNAP-Ed). Methods Households with incomes ≤185% of the federal poverty level were randomly selected in 2018 and 2019. A study introduction letter in English or Spanish was sent to each household. Next, bilingual staff verified household eligibility by phone, and the youngest mother/caregiver of children and one child 5 to 11 years. During the subsequent interviews, bilingual staff administered the Automated Self-administered 24-Hour Dietary Assessment Tool (ASA24) in English or Spanish. The quantity and size of each reported food and beverage item was determined by asking mothers to reference pictures in a study-provided portion-size booklet or measuring cups or spoons. The procedures were replicated to obtain 24-hour dietary information for children. HEI-2015 scores were calculated based on established procedures from 13 components of dietary intake. In line with previous studies, “weekend” represented the 24-hour dietary recall period occurring on a Friday, Saturday, or Sunday. HEI-2015 scores were regressed for the complete samples, and Latinx, African American, and white mothers and children separately. Covariates were age, education for mothers, gender for children, and number of telephone recruitment attempts leading to and including the two completed interviews per household. Results Complete and paired data were available for 4,166 mothers and children. Mean HEI-2015 scores for mothers was 58.9 (95% CI = 57.8,60.0) and for children was 54.9 (95% CI = 54.0,55.8). For the complete samples, diet quality was poorer on weekends: mothers: B = −1.43 (95% CI = −2.30, −0.564); children: B = −1.58 (95% CI = −2.43, −0.736). However, within racial/ethnic group analyses revealed only Latinx mothers and children to have poorer weekend versus weekday diets. Conclusions Studies of Latinx mothers and their children should investigate reasons for poorer diets on weekends, and such factors should be incorporated into SNAP-Ed and other nutrition interventions directed at Latinx families. Funding Sources California Department of Social Services.