Despite the prominence of the building from the air, the building emerged unscathed in February 1941 during the Swansea Blitz of the Second World War.[8]
On 3 July 1969, The Prince of Wales made an announcement in person at the Guildhall that the town of Swansea would become a city.[10]
The west wing of the building was used as the venue for the Swansea assizes.[11] Following the implementation of the Courts Act 1971, the former assizes courthouse became the venue for hearings of the newly designated Swansea Crown Court.[12] Crown court hearings then moved to a dedicated courthouse in St Helen's Road in 1988.[13]
In the 1980s, the first recorded urban breeding pair of peregrine falcons was observed nesting on the Swansea Guildhall.[14]
For most of the 20th century, the Guildhall was also the meeting place of Swansea City Council; however, it ceased to be the local seat of government when the enlarged City and County of Swansea Council was formed at Swansea Civic Centre in 1996.[8] It continues to accommodate the city's law courts and also the council's administration offices.[8] The Guildhall clock was last overhauled in 2019.[15]