Mae adran 77 o Ddeddf Treth Trafodiadau Tir a Gwrthweithio Osgoi Trethi Datganoledig (Cymru) 2017 yn gosod rhwymedigaeth statudol ar Weinidogion Cymru. Gofynnir iddynt wneud trefniadau ar gyfer adolygiad annibynnol o dreth trafodiadau tir o fewn 6 blynedd i’r dyddiad y daeth adran 77 i rym – gyda dyddiad cau o 24 Mai 2023.
Section 77 of the Land Transaction Tax and Anti-avoidance of Devolved Taxes (Wales) Act 2017 places a statutory obligation upon the Welsh Ministers to make arrangements for an independent review of land transaction tax (LTT) within 6 years of section 77 coming into force – a deadline of 24 May 2023.