Trustworthy conversational agents (CAs) can help older adults (OAs) as a flexible means to access basic services such as online banking where the shift to CAs is fast. However, OAs tend not to adopt CAs due to the lack of trust and cannot benefit from them. Consequently, OAs may become digitally marginalised and excluded from digitalised society. It is timely to study with interdisciplinary approaches how design choices of CAs (modality, embodiment, anthropomorphism) and OAs’ mental models, attributes (e.g., gender) and conditions (e.g., loneliness) are related to trust in CAs. Design guidelines and prototypes for OA-specific CAs will be delivered.