Background: The inter‐jurisdictional National Mutual Acceptance (NMA) scheme for Human Research Ethics Committee (HREC) approvals of human research is designed to reduce the reported delays and costs of ethical review. Introduction of the NMA set forth an uncoupling of the ethics and governance review processes, permitting a single ethical review for multiple sites, while continuing separate governance review for each centre covering financial and operational aspects of the research project.

Aim: To compare the time required to gain ethics and governance approvals in Australia for a non‐interventional investigator‐led study from December 2015 to approval times for an earlier pre‐NMA study utilising a similar study design and study sites and evaluate the effect that the NMA has had on total approval time for non‐interventional multi‐centre projects.

Methods: We recorded the time taken to obtain ethics and governance approval at 16 sites for our nationwide low‐risk non‐interventional study looking at the prevalence and aetiology of non‐tuberculous mycobacterial infection in people with cystic fibrosis in Australia.

Results: Applications were submitted to three hospitals and one university HREC to conduct our study at 16 hospital sites, HREC approval took from 16 to 79 days (median 28). Subsequent site‐specific governance approval at 15 hospital sites took 23–225 days (median 83). The entire process of gaining ethical and governance approval to conduct the study at 16 sites took 24 months at an estimated cost of AU$56000(US$ 42 000).

Conclusion: Lengthy governance approval processes negate benefits gained from centralised ethics review under the NMA.