Three quarters of UK adults expect online queries to be dealt with the same day – and half expect a reply within the hour, new research has revealed.

When the same study was conducted in 2014, only 67% of respondents expected a response the same day and 30% within the hour.

According to Lithium Technologies, which conducted the research, the findings reflect how younger tech-savvy generations are driving up expectations in online customer service.

The survey of more than a 1,000 consumers also shows the extent to which brands are falling short in satisfying their consumers.

Millennials (aged 18 to 24) were by far the most demanding generation in the study, with 55% of respondents expecting a response within the hour, compared to 41% of people aged 35 to 54.

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Men are the more demanding gender when it comes to customer service demands, the study found – with 23% expecting a near immediate response to a query, compared to 15% of women.

Further evidence shows that customer service habits are changing, especially when it comes to the preferred method of contact. Three in five survey respondents said they only call a 0800 or other toll-free numbers for customer service issues as a last resort.

“As technology has evolved, so too has the need for immediacy in customer communications,” said Fabrice Etienne, marketing director at Lithium Technologies, EMEA. “Brands need to do more to meet their customers’ expectations by engaging them online, or risk losing them to more digitally-advanced companies.”