Background/Objective: This study examined for the first time in Greece, the estate planning and advance care planning (ACP) of healthy older adults and older patients diagnosed with different types of neurocognitive disorders for the presence of a valid will, a durable power of attorney for healthcare, and a living will, while the associations between general cognition, education, depression, actual financial capacity, and demographic and socioeconomic characteristics were examined. Methods: A total of 543 participants were examined with neuropsychological tests including Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS). Along with the neuropsychological examination, all participants responded to relevant ACP questions. Results: Surprisingly, the majority of the participants regardless of their diagnostic group did not have a valid will, had not assigned a durable power of attorney for healthcare, and had not a written living will. Logistic regression revealed that biological sex, age, education, marital status, diagnostic group, MMSE, GDS, and actual financial capacity as measured with LCPLTAS did not predict the existence of a valid will, durable power of attorney, and written living will. Conclusions: A diagnosis of AD is not associated with more engagement in ACP as supported by research in USA. Concerns are raised about possible exploitation and abuse of older patients.