Regular and frequent testing is a good way for HIV infection to be identified before a substantial decline in CD4 count. While there has been a significant rise in the uptake of HIV testing in recent years, the 2010-12 National Survey of Sexual Attitudes and Lifestyles found that among men who have sex with men, only 27% had tested in the previous year and 52% had done so in the past five years. Less than half the black African men (44%) and black African women (46%) had tested in the previous five years. Across all demographic groups, people with more sexual partners were more likely to have tested.

Public Health England recommends that MSM should have an HIV test at least once a year, and every three months if having unprotected sex with new or casual partners. The National Institute for Health and Care Excellence (NICE) has a similar recommendation.

In relation to black African and Caribbean people, PHE recommends that individuals who have unprotected sex with new or casual partners should test regularly, but the frequency is not defined. The National AIDS Trust has argued for a recommendation of an annual test for all sexually active African people in the UK.

But some researchers suggest that these recommendations are too conservative and that frequency of testing needs to be based more precisely on the incidence of new infections in a community. A mathematical model based on the American health system found that, in a community with an incidence of 0.01%, the most cost-effective testing frequency is once every 2.4 years. If the incidence is 0.1%, testing should occur every nine months. In a community with an incidence of 1%, the optimal testing frequency is every three months. Reliable estimates of incidence among African people in the UK are currently lacking, but may be around 0.5% in MSM.