Families of children with autism spectrum disorder (ASD) endure significant financial and employment burden because of their children's numerous needed services. The study objective is to describe additional impact on families of children with intellectual disability (ID) in addition to ASD. The study is a secondary data analysis of the 2009-2010 National Survey of Children with Special Health Care Needs. Children whose parents answered "yes" when asked whether their child had ASD or ID were classified as having ASD alone (unweighted n = 2,406), ID alone (unweighted n = 1,363), or both ASD/ID (unweighted n = 620). Bivariate and multivariate analyses compared study outcomes of family financial and caregiver burden using ASD as the reference group. All analyses were weighted using person-level estimates. Of children with ASD, 24% also had ID. More than half of caregivers of children with ASD/ID reported financial difficulty (52%) and having to stop work to care for their child (51%). Compared with ASD alone, caregivers of children with both ASD/ID were more likely to report financial difficulty (aOR 1.65, 95% CI 1.10-2.46), cutting work hours (aOR 1.43, 95% CI .98-2.08), and stop working (aOR 2.32, 95% CI 1.57-3.43). No differences were found between caregivers of children with ASD only and ID only. We conclude that having ID in addition to ASD may be associated with greater negative impact on family financial and employment burden. Recognition of ID in addition to ASD is important to tailor the clinical approach and sufficiently support families.