OBJECTIVE: To examine the relationship between HIV risk behaviour, risk perception and testing in Britain. DESIGN: A probability sample survey of the British population. METHODS: We analyzed data on sexual behaviour, self-perceived HIV risk and HIV testing (excluding testing because of blood donation) from 13 751 sexually experienced men and women aged 16-74, interviewed between 2010 and 2012 using computer-assisted face-to-face and self-interviewing. RESULTS: Altogether, 3.5% of men and 5.4% of women reported having an HIV test in the past year. Higher perceived risk of HIV was associated with sexual risk behaviours and with HIV testing. However, the majority of those rating themselves as 'greatly' or 'quite a lot' at risk of HIV (3.4% of men, 2.5% of women) had not tested in the past year. This was also found among the groups most affected by HIV: MSM and black Africans. Within these groups, the majority reporting sexual risk behaviours did not perceive themselves as at risk and had not tested for HIV. Overall, 29.6% of men and 39.9% of women who tested for HIV in the past year could be classified as low risk across a range of measures. CONCLUSION: Most people who perceive themselves as at risk of HIV have not recently tested, including among MSM and black Africans. Many people tested in Britain are at low risk, reflecting current policy that aims to normalize testing. Strategies to further improve uptake of testing are needed, particularly in those at greatest risk, to further reduce undiagnosed HIV infection at late diagnoses.