The average tax due per residential transaction was lowest in Blaenau Gwent (£1,820) and Neath Port Talbot (£2,190).
Roedd y dreth gyfartalog a oedd yn ddyledus fesul trafodiad preswyl ar ei isaf ym Mlaenau Gwent (£1,820) a Chastell-nedd Port Talbot (£2,190).