Three-quarters of people say they've gone online more during the coronavirus lockdown - but a third say their internet is slower than before.
According to a YouGov survey, 73% said they were spending more time using the internet as the nation attempts to work from home, go to school remotely or just keep in touch with loved ones.
And 28% said they have experienced worse internet performance - and 7% described it as much worse - despite recent suggestions that broadband providers have largely held up against the surge in demand.
Seven in 10 (69%) of people who experienced connectivity issues said it affected general online activities, followed by streaming at 67%, video calls at 59% and work-related tasks at 52%.
However, over half (57%) of the 2,301 participants questioned said they noticed no change in the performance of their home internet connection.
Olivia Bonito, digital media and technology research manager at YouGov, said: "New YouGov research shows that the internet had become even more important to daily life during the coronavirus lockdown, with Britons using their household broadband connection for entertainment and to work from home."
"Of course this means that many are now using their internet much more than usual but a significant proportion - a third - are experiencing worse internet performance than they did prior to the lockdown.
"This difficulty in accessing stable internet increases as the number of household residents rises, suggesting internet performance is being affected by increased demand.
"While many might be able to cope in the short term, it could start to affect productivity if working from home becomes the 'new normal'."
Last month, analysis by regulator Ofcom suggested that download speeds have only fallen by an average of 2% since lockdown began in the UK.
