The Office for National Statistics (ONS) has published Census 2021 data on the number and location of second addresses (ONS), including those used as holiday homes.
Mae'r Swyddfa Ystadegau Gwladol wedi cyhoeddi data Cyfrifiad 2021 ar nifer a lleoliad ail gyfeiriadau, gan gynnwys y rhai a ddefnyddir fel cartrefi gwyliau.