Currently, there are limited circumstances when a formal challenge to a Council Tax band can be made as the current property bandings have existed for a long time, since April 2005.
Ar hyn o bryd, dim ond o dan amgylchiadau cyfyngedig y gellir herio band Treth Gyngor yn ffurfiol am fod y bandiau eiddo presennol wedi bodoli am amser hir, ers mis Ebrill 2005.