Although there is no on site parking at Sheffield City Hall, there are plenty of city centre car parks within easy walking distance.
The venue recommends Q Park on Rockingham Street (S1 4NL), which is £3.90 for up to 3 hours, or a flat rate of £2 on Sundays. It's a 5-10 minute walk at buggy pace to the venue from this car park.
There are limited car parking areas for blue badge holders on streets close to the City Hall.
You can find all other parking options near the venue on the Parkopedia website.