The claim is made by setting off the amount of the credit against the amount of tax that person would otherwise be required to pay under section 42(1) of LDTA.
Gwneir yr hawliad drwy osod swm y credyd yn erbyn swm y dreth y byddai fel arall yn ofynnol i'r person hwnnw ei dalu o dan adran 42 (1) o'r DTGT.