Despite a surge in use in Snapchat and Instagram alongside Facebook’s longer established popularity, 26% of respondents said they ignore social posts or ads from brands on social.
Kantar TNS’ Connected Life study found that many consumers feel bombarded by brands on social platforms, with 34% saying they feel "constantly followed" by online advertising.
Scepticism appears to be highest in Scandinavian countries, with 57% saying they actively ignore content from brands.
Meanwhile, 15% in Saudi Arabia and 19% in Brazil said they would avoid branded content.
China and South Africa sit closer to the global average, with 24% and 26% respectively saying they would ignore brands on social.
Almost a quarter (23%) of internet users are now on Snapchat, compared to 12% two years ago. Instagram has also seen a surge in popularity, with global usage rising to 42% from 24% in 2014.
Connected Life is a study of digital attitudes and behaviours of 70,000 internet users across 57 countries between June and September this year.
It also found Poland to be the country where internet ad-blocking is most prevalent (51%), way ahead of the global average of 18%.
Michael Nicholas, global director at Kantar TNS, said: "The rise of Instagram and Snapchat taps into people’s desire for instant, entertaining content from friends, peers and influencers, often enhanced by fun filters and editing. There is a real opportunity for brands to tap into this trend by creating 'personalisable' and shareable content, such as videos and stories. The challenge is how to focus the right content to the right people, on the right platforms and at the right moments.
"Some brands are getting it spot on – in the past year we’ve seen the likes of Disney, Starbucks and McDonald’s use Snapchat’s filters to engage consumers in a way that doesn’t feel intrusive. This is key to overcoming many people’s fundamental negative perceptions of brand activity online."