Background Suicide ideation and suicide attempts represent a public health problem in Australia, for which most people do not seek formal clinical care. However, little research currently exists on the prevalence of STB within the culturally and linguistically diverse (CALD) community, and whether the help-seeking behaviours of CALD persons differs from non-CALD persons.Methods This is a secondary analysis of data from the National Study of Mental Health and Wellbeing, which surveyed a representative sample of Australian residents aged 16–85 years (N = 15,882) between December 2020 and October 2022. The prevalence of lifetime suicide ideation and suicide attempts by region of birth were calculated, and latent class analysis was used to examine patterns in both formal and informal help-seeking for both suicide ideation and suicide attempts separately. Logistic regression models were used to identify and quantify associations between region of birth and likelihood of class membership.Results Of the sample, 2602 (16.4%) reported suicide ideation and 753 (4.8%) people reported a suicide attempt. The prevalence of both was generally higher in the Australian-born population (18.3%), and lowest in people born in South Asia (5.9%). Most people reported no, or limited, use of clinical services for suicide ideation (76%) or suicide attempt (60%). People born in East Asia and the Pacific or Sub-Saharan Africa were 55% less likely and 70% less likely, respectively, to seek help from clinical services for suicide ideation compared to Australian-born people. People with moderate English proficiency were 92% less likely than people with native English proficiency to seek help from clinical services following a suicide attempt.Conclusions Most people in this sample were did not use clinical services for suicide ideation or suicide attempts. This is particularly so for persons born in East Asia and the Pacific or Sub-Saharan Africa. There is a need to understand and address social and cultural factors which may prevent people from these regions from engaging with clinical services. The CALD population in general may benefit from enhanced cultural responsiveness from clinical services, including the use of bicultural support workers and interpreters to improve help-seeking from clinical services.