Background Affected family members (AFMs) are impacted by a significant other’s drug, alcohol, or behavioural addictions, and deserve support in their own right. The aim of this study was to describe AFMs seeking treatment and the support received.

Methods Referral data (2010–2020) for AFMs seeking treatment because of being affected by another’s drug, alcohol, or behavioural addictions were analysed descriptively in this cross-sectional study (n = 13,744). The data are from an existing Irish health surveillance system.

Results Referrals were mostly females (77.5%) aged 35–54 years (38.9%). Children and young adults each accounted for 6.5% of referrals. Adults mostly lived with children (61.7%) and self-referred (63.1%). Children mostly lived with family (93.2%) and were referred through social/community services (42.0%) and family/friends (40.7%). Individual counselling and brief intervention were the main treatments for adults and children. Among adults, the highest median treatment duration was for group counselling (120 days); among children, it was individual education/awareness programmes (165 days).

Conclusions Findings demonstrate the demand for services for AFMs, and highlight the need for services for women, children, and young adults. Routine surveillance is a valuable source of data and could include further items on AFMs seeking personal support and supporting others through addiction treatment.