Both residential and day programs for eating disorders provide options for a step-up from standard outpatient care. However, there have not been any direct comparisons of their effectiveness and limited research on predictors of better outcomes from either setting. This study aimed to compare clinical outcomes and predictors from a transdiagnostic residential and day program for eating disorders. Measures of eating disorder symptoms, body mass index (BMI), anxiety, and depression were completed by 106 participants (n = 82 residential, n = 24 day program) at pre-treatment, after four weeks, and at discharge. Greater improvement from pre- to post-treatment was evident from residential, compared to day program, treatment (all ps ≤ .005, medium effect sizes). After accounting for age, baseline BMI, and treatment duration, lower baseline eating disorder symptoms (β = 0.84, p < .001) and greater early change in eating disorder symptoms (β = -0.88, p < .001) each predicted less severe eating psychopathology at discharge. Longer treatment duration predicted better post-treatment outcomes for the day program, but was less predictive of residential outcomes (β = 0.64, p < .001). Post-treatment outcomes were not predicted by age or baseline BMI, anxiety, or depression. As symptom severity did not differ at baseline, results support residential treatment over day programs for individuals with more severe eating disorder presentations. Future research should examine whether day programs are equally effective as residential treatment at lower baseline symptom severity and compare residential care with more intensive settings such as inpatient services.