Abstract Background Self-care is a key component of current policies to manage long term conditions. Although most people with long-term health problems care for themselves within lay networks, consultation rates for long-term undifferentiated illness remain high. Promotion of self-care in these individuals requires an understanding of their own self-care practices and needs to be understood in the context of health care pluralism. The aim was to investigate the extent and nature of self-care practices in patients experiencing long term health problems, sources of information used for self-care, and use of other forms of health care (conventional health care and complementary and alternative medicine). Methods The study involved a cross-sectional community-based survey set in three general practices in South West England: two in urban areas, one in a rural area. Data were collected using a postal questionnaire sent to a random sample of 3,060 registered adult patients. Respondents were asked to indicate which of six long term health problems they were experiencing, and to complete the questionnaire in reference to a single (most bothersome) problem only. Results Of the 1,347 (45% unadjusted response rate) who responded, 583 reported having one or more of the six long term health problems and 572 completed the survey questionnaire. Use of self-care was notably more prevalent than other forms of health care. Nearly all respondents reported using self-care (mean of four self-care practices each). Predictors of high self-care reported in regression analysis included the reported number of health problems, bothersomeness of the health problem and having received a diagnosis. Although GPs were the most frequently used and trusted source of information, their advice was not associated with greater use of self-care. Conclusions This study reveals both the high level and wide range of self-care practices undertaken by this population. It also highlights the importance of GPs as a source of trusted information and advice. Our findings suggest that in order to increase self-care without increasing consultation rates, GPs and other health care providers may need more resources to help them to endorse appropriate self-care practices and signpost patients to trusted sources of self-care support.