Sanxenxo has a permanent population of around 17,000 people, though this number can increase dramatically during the summer months as tourists flock to the town. The population is predominantly Spanish, with a growing number of international visitors and second-home owners contributing to its cosmopolitan atmosphere during peak seasons.
The town has seen steady population growth in recent years, particularly due to its increasing popularity as a tourist destination and its appeal to retirees seeking a peaceful coastal retreat.