39% of British internet users use ad blocking technology

"Four in ten (39 per cent) of UK Internet users use ad-blocking technology to curb the number of promotions they see while browsing as they become increasingly dissatisfied with the types of ads on show, according to a new study.
It’s not surprising then that many publishers are “abandoning the old models in favour of new ‘native’ advertising or sponsored content”, according to Reuters Digital News Report. Consumers are becoming more apathetic to online ads and increasingly searching for ways to screen them out of their experience, the report concluded, which is part of a fundamental shift in how they interact with brands online.
A third (39 per cent) of people in the UK say they ignore ads, while in the US the figure was slightly slower at 30 per cent. Around three in ten (31 per cent) consumers in the UK said they actively avoid sites where ads interfere with the content. In the US, one in two consumers do the same thing and nearly half (47 per cent) of them revealed they now use ad blocking software."

Source:  The Drum, 20th June 2015
Also - The IAB & YouGov put the figure at 15% of UK internet users; 22% of men, and 9% of  women, with penetration highest among 18-24 (34%) and 25-34 year olds (19%)
Also - Over 1m Australians
Also - 20% in Europe & US, according to Sourcepoint
Also - 24% in US on PC, but only 3% on mobile, according to Genesis Media