Sefydlwyd yr Awdurdod ym mis Hydref 2017, a hynny chwe mis cyn i ddwy dreth ddatganoledig gyntaf Cymru ers 800 mlynedd – y dreth trafodiadau tir a’r dreth gwarediadau tirlenwi – gael eu cyflwyno ar 1 Ebrill 2018.
The WRA was established in October 2017, 6 months ahead of the introduction of first 2 devolved Welsh taxes in 800 years – land transaction tax (LTT) and landfill disposals tax (LDT) from 1 April 2018.