Waiting lists in mental health services are currently considered too long. Lengthy waits of up to 18 weeks are commonly reported in the UK. Waiting lists have long been associated with a variety of negative psychological responses, however there is little understanding behind young adults’ personal experiences of such delays within mental health services. The current study aimed to explore young adults’ experiences of waiting lists in mental healthcare in the UK. Seven young adults were interviewed in the current study (aged 19–22). Interpretive phenomenological analysis was utilised to explore participant accounts. Three super-ordinate themes were generated: Reliance on Alternative Methods of Support; Inability to Function Sufficiently; and Emergence of Negative Beliefs, Emotions and Thoughts. Participants primarily reported a variety of negative psychological and behavioural consequences associated with waiting lists in mental health services, as well as exacerbated existing physical and psychological health issues. In accordance with the limited number of previous studies, waiting lists are considered by patients to be barriers to mental health support and intervention. Future direction is advised.