According to a report that will be presented to the authority on Wednesday, many businesses and media outlets had also started referring to the mountain and national park by their Welsh names.
The authority said this had resulted in “increasing consistency and visibility of the Welsh identity associated with the park”.
Gwynedd councillor John Pughe Roberts had earlier put forward a motion asking the park to stop using Snowdon and Snowdonia, claiming many were “complaining that people are changing house names, rock names, renaming the mountains”.
Citing the use of Welsh names “aligned with the authority’s commitment to promoting the Welsh language” and of “heritage preservation”, officers also reported the move represented a “unique selling point” which “sets it apart from other UK national parks”.