The 31-year-old singer was arrested by police on 2 December 2016 the morning after performing in the city.
An allegation of rape and sexual assault was made by a 20-year-old woman following the concert at a nightclub.
A statement released at the time of the pop star’s arrest, by his representatives from 10 Worlds Music UK, which looked after Williams, said the singer denied the accusations.
West Midlands Police said Williams, from Croydon in London, has now been charged with rape.
A second man – Jamien Nagadhana, also aged 31, from Hounslow in London, has been charged with sexual assault.
Both will appear at Walsall and Aldridge Magistrates Court on 11 October.
Williams found fame on television talent show the X Factor in 2008, but has pursued a solo career since pop/R&B boyband JLS broke up in 2013.