The Welsh Language Use Survey 2019-20 was carried out as part of the National Survey for Wales, in similar fashion to the Welsh Language Use Survey 2013-15.
Cafodd Arolwg Defnydd Iaith 2019-20 ei gynnal fel rhan o Arolwg Cenedlaethol Cymru, yn yr un modd ag Arolwg Defnydd Iaith 2013-15.