Background: Having a child on the autism spectrum (AS) is known to impact caregiver quality of life (QoL), time use, and stress. A co-occurring diagnosis of intellectual disability (ID) is common among children on the autism spectrum, with ID itself impacting caregiver outcomes. Method: This study sought to understand how co-occurring ID in children on the autism spectrum may influence caregiver-related outcomes. Secondary analysis of survey data from caregivers of 278 children on the autism spectrum with (n = 62) and without (n = 216) co-occurring ID was conducted, exploring impacts on caregiver QoL, stress, coping, and time-use. Results: Univariate analysis showed that caregivers of children on the autism spectrum with co-occurring ID reported greater levels of stress due to core symptoms and co-occurring physical conditions, and had different time use patterns then caregivers of children on the autism spectrum without co-occurring ID. Multivariate analysis, however, showed that caregivers of children on the autism spectrum with and without co-occurring ID differed only in the time they spent preparing meals, socialising with friends and accessing in-home respite care. Conclusions: The presence of co-occurring ID in children on the autism spectrum had limited impacts on caregiver-related outcomes. Families of children across the entire AS require adequate supports.