The Office of National Statistics say 1.5% including females.
Deduct the females who are hardly affected at all by HIV and you have a figure of around or just under 1%.
The ONS study was of over 250,000 people, a huge sample for statistical purposes.

A new study conducted by the Center for Disease Control and Prevention (CDC) highlights urgent HIV prevention needs for have sex with men, especially young men and men of colour.

Approximately one in five (19 percent) men who have sex with men (MSM) in a study of 21 major U.S. cities is infected with HIV, and nearly half (44 percent) of those men are unaware of their infection, according to a new analysis from the Centers for Disease Control and Prevention. In the study, young MSM and MSM of color were least likely to know their HIV status.
The findings were recently published in CDC's Morbidity and Mortality Weekly Report