Health literacy (HL) and eHealth literacy (eHL) can facilitate carers of people with dementia (PwD) to search, find, assess and apply information related to dementia‐specific issues from different resources. There is a lack of research with regard to HL and eHL among carers of PwD. The aim of this study is to identify the levels of HL and eHL among carers of PwD in Greece and Cyprus and to search for the associations with other caring concepts. This study followed a descriptive correlational design. In total, 174 primary informal carers of PwD, mostly women, over 45 years old and with more than 12 years of education and 67 secondary carers (family, friends or neighbours) participated in the study. Primary informal carers completed a face‐to‐face survey on the level of HL and eHL, internet use, dementia‐specific internet use, care‐giving self‐efficacy, coping strategies, care‐giving perceptions and social support. Primary informal carers reported a high level of eHL and HL. Carers with higher HL were more likely to report higher score of eHL, care‐giving self‐efficacy and lower score of problematic/dysfunctional coping. Higher score of eHeals‐Carer "information seeking" was related with higher use of emotion‐focused strategies. From this study, a positive message was received with regard to the role of HL and eHL in the everyday caring life. Non‐for‐profit organisations and healthcare professionals could integrate in their practice assessment tools and develop tailored training courses for carers enhancing low level of HL and eHL. [ABSTRACT FROM AUTHOR]