While the Zika virus (ZIKV) is not endemic in Australia, it continues to be prevalent in many neighbouring countries in the Indo-Pacific region. It poses significant public health concerns due to its association with severe outcomes, including Guillain-Barre syndrome and congenital malformations such as microcephaly. Although vector-borne transmission is the primary route, sexual transmission has been documented, raising the possibility of unrecognised and underreported infections. We report the details of 2 cases of ZIKV infection diagnosed in the Northern Territory of Australia. The first case was a male traveller who contracted the virus in Timor-Leste and the second, his female partner in Australia. We believe this represents the first reported incidence of sexually transmitted ZIKV infection acquired in Australia. The investigation emphasizes the importance of obtaining detailed patient histories, including sexual histories, to improve detection and understanding of ZIKV transmission. It also highlights the challenges of diagnosing ZIKV due to its nonspecific symptoms and the necessity of public health education regarding ZIKV transmission and prevention strategies. Clinicians need to be aware of the symptoms, geographic distribution and transmission modes of infectious diseases like ZIKV in returned travellers, as well as the potential implications for their contacts. Heightened awareness is important to ensure early detection, appropriate management, and counselling to prevent transmission.