INTRODUCTION: Perceived lack of confidential health care is an important barrier for young people accessing health care services in New Zealand (NZ). AIM: To determine the prevalence of forgone health care among a nationally representative sample of NZ secondary school students and to describe the health concerns and specific health issues for which young people had difficulty accessing health care. METHODS: Random sample of 9107 NZ secondary school students participated in a 2007 health survey using internet tablets. Questions about access to health care included whether there had been a time when they had not accessed health care when needed, reasons for difficulty in accessing health care, current health concerns and health risk behaviours. RESULTS: One in six students (17%) had not seen a doctor or nurse when needed in the last 12 months. Female Maori and Pacific students and those living in neighbourhoods with high levels of deprivation were more likely to report forgone health care. Students with chronic health problems, those engaging in health risk behaviours or experiencing symptoms of depression were more likely to report being unable to access health care when needed. Students reporting privacy concerns were more likely to report difficulty accessing health care for sensitive health issues, such as sexual health, emotional problems, pregnancy-related issues, stopping cigarette smoking, or alcohol or drug use. DISCUSSION: NZ secondary school students who forgo health care are at increased risk of physical and mental health problems and in need of accessible and confidential health services. KEYWORDS: Access to health care; adolescent health services; general practice; preventive health services