If none of these are available, contact the Subsidy Control Unit (subsidycontrolunit@gov.wales) to confirm an appropriate identifier.
Os nad yw’r un o'r rhain ar gael, cysylltwch â'r Uned Reoli Cymorthdaliadau (YrUnedRheoliCymorthdaliadau@llyw.cymru) i gadarnhau beth fyddai’n god adnabod priodol.