The integrity and function of the gastrointestinal system is important in disease prevention and management. This study aims to describe the management methods used by Australian adults with suspected increased intestinal permeability (IP) and the association with subjective wellbeing (SWB) and health-related quality of life (HRQoL). Cross-sectional survey of Australian adults diagnosed with IP or have suspected (undiagnosed) IP. Questionnaire items investigating demographic characteristics, self-reported outcome of IP and treatment methods used to manage IP. Participants' HRQoL and SWB according to the 20-Item Short Form Health Survey (SF-20) and Personal Wellbeing Index-Adult (PWI-A) scale, respectively. Participants ( = 589) frequently used dietary products (87.9%), dietary supplements (72.9%) and lifestyle therapies (54.6%) for managing IP. Participants had lower (i.e., worse) mean SWB scores for all domains compared to the Australian population ( < 0.001). The number of days IP reported to affect daily living was negatively correlated with SWB and HRQoL ( < 0.001). Participants that reported an improvement in their IP in the previous 12 months were more likely to be treated by a healthcare practitioner (OR = 2.04,  = 0.015), use dietary supplements (OR = 2.66,  = 0.003), participate in vigorous exercise (OR = 2.99,  < 0.001) and employ vagus nerve stimulation (OR = 3.10,  = 0.010). Conversely, they were less likely to consume gluten (OR = 0.35,  < 0.001) or use nonsteroidal anti-inflammatory drugs (OR = 0.35,  = 0.022). Self-reported improvement of IP (β = 10.70,  < 0.001) and use of dietary products (β = 12.12,  = 0.008) were predictors of a higher level of SWB. Altered IP may pose a greater health burden than previously thought, with poor SWB and HRQoL reported in Australian adults with self-reported IP. Our results highlight the potential clinical relevance and consequence of altered IP, providing the first indication of a possible relationship between altered IP and both SWB and HRQoL.