Although social support is commonly investigated in the context of substance recovery, researchers have widely neglected its multilevel nature, thus limiting what we know about its measurement across levels of observation. The current study used multilevel confirmatory factor analyses (MCFA) on 229 individuals living in 42 recovery homes to investigate the structure of single factor of social support at the individual and house-levels. Multilevel structural equation model (MSEM) was then conducted to examine whether the social support factor was associated with stress at the individual and house-levels. MCFA results showed that within individuals, all social support measures were significant and positive while at the house-level, there were a few discrepancies (e.g., IP was negative). Stress was significantly negatively related to the social support factor at the individual-level, but this association was positive at the house-level. These findings suggest that on an individual-level, a person's perception and source of social support is particularly important -even if the source of support comes from someone who is not abstinent. On a house-level, social support is more sensitive to outside influences than within individuals. Implications for future research and substance use interventions targeting social support are discussed.