Penalties are charged on the late receipt of tax returns and late payments or for other reasons allowed under the Tax Collection and Management (Wales) Act 2016.
Codir cosbau pan fydd ffurflenni treth yn cael eu derbyn yn hwyr, os bydd taliadau’n hwyr, neu am resymau eraill a ganiateir o dan Ddeddf Casglu a Rheoli Trethi (Cymru) 2016.