This is where taxpayers have submitted a downwards amendment to the LTT due on a tax return, but where we believe they were incorrect to do so.
Mae hyn lle mae trethdalwyr wedi cyflwyno diwygiad am i lawr i’r dreth sy'n ddyledus ar ffurflen dreth, ond lle rydym ni’n credu eu bod yn anghywir i wneud hynny.