Rydym yn defnyddio cwcis i wella eich profiad ar ein gwefan. Am wybodaeth am y cwcis yma a sut i’w dileu, darllenwch ein polisi cwcis.
Help and advice with your phone and broadband services.
Negeseuon a galwadau niwsans
Gwiriwr band eang a symudol Ofcom
UK Calling
Beth yw rhifau 03?
Cloi a datgloi ffonau symudol
Canllaw Cod Cyflymderau Band Eang
Learn more about call costs, billing problems and using your phone abroad, as well as advice if you're considering switching
