Getting married in a register office or town hall
309 of the 7,163 approved premises in England and Wales are register offices, town halls, guildhalls and other civic buildings. They are a distinct kind of venue and they are easy to overlook, because they are the ones no wedding directory has any reason to promote.
Two different things share the name
The register office is where births, deaths, marriages and partnerships are registered — an administrative office. Many of them also have a room approved for ceremonies, which is what puts them on this list. Town halls, civic centres and guildhalls are the same idea at a larger scale: a municipal building with a room in it that a council has approved.
Some are genuinely handsome buildings. A Victorian guildhall or a 1930s civic hall is a room with more character than a lot of what gets marketed as a wedding venue.
Finding them
Every area page on this site has a Register offices & town halls filter above the list, which narrows it to exactly this set for that area. They are matched by name — a building called a register office is a register office — so the filter is reliable in a way a general "venue type" guess would not be.
They are spread thinly and evenly: most council areas have one or two rather than a cluster, which is the opposite of how the rest of the list is distributed.
One thing this site cannot tell you
Nothing here covers what a ceremony costs, how far ahead you can book, or how any individual council runs its diary. That is 175 different answers which change without notice, and inventing a general one would be worse than useless. The entry names the council; ask them.