The main purpose of revaluation, and the associated setting of the multiplier, is to adjust the liability of properties relative to others within the non-domestic rates (NDR) tax-base.
Prif ddiben ymarfer ailbrisio, a gosod y lluosydd yn gysylltiedig â hynny, yw addasu rhwymedigaeth eiddo o'i gymharu ag eraill o fewn sylfaen drethu ardrethi annomestig.