This study explores the experiences and outcomes associated with the use of an autism alert card, developed to assist with the complexities of autism disclosure. A mixed-methods approach was employed, surveying 272 Australian participants, including 136 Autistic adults, 128 parents or caregivers of Autistic children and eight Autistic children. Our research aimed to understand who is using the alert card, in what contexts and the differences in perceptions of the card between Autistic individuals and their parents. Findings indicate that about half of the participants used the card, primarily in public settings such as transport (17%), healthcare (16%) and retail (16%). The card was seen as a valuable tool for facilitating communication, reducing the need for verbal explanations and providing a sense of security. However, challenges were reported, including societal disbelief, patronising attitudes and internalised stigma, highlighting the need for greater public education on autism. Despite these challenges, majority of participants (76.2%) would recommend the card. This research underscores the dual nature of autism alert cards as both beneficial and limited by societal attitudes, emphasising the need for comprehensive training and awareness programmes to maximise their effectiveness.