Mobile and fixed-line call volumes declined in the UK for the first time last year as people opted to communicate via social networking sites and text messaging hit a record high.
The average number of texts sent per person climbed to 200 a month, a 16.6 per cent rise on the previous year, while total mobile telephone calls fell 1.1 per cent to 124bn minutes. The number of texts sent has more than doubled over the past four years.
The findings, contained in the latest annual Communications Market Report by Ofcom, the industry regulator, coincide with increasing use of internet-enabled smartphones and tablet computers.
Smartphones are owned by two-fifths of the population and 11 per cent of households own a tablet.
"Our research reveals that in just a few short years, new technology has fundamentally changed the way we communicate," said James Thickett, Ofcom's director of research.
"Talking face to face or over the phone are no longer the most common ways for us to interact with each other."
There was a marked divergence in communication patterns between age groups, with 90 per cent of 16- to 24-year-olds texting friends and family at least once a day compared with 15 per cent of over-65s.
Landline voice calls were still the most popular means of communication among the over-65s, with 42 per cent making at least one landline call a day to friends and family.
Social networking was the second most popular form of communication for 16- to 24-year-olds, with 74 per cent communicating with family and friends at least once a day in this way.
The rise in smartphone sales has been a key driver of change, particularly among young people. More than 40 per cent of smartphone owners said the device was their most important means of accessing the internet.
Across the population as a whole, the average user spends 2.1 hours a month browsing mobile internet, a near 25 per cent rise on 2010.
Smartphone ownership is also revolutionising shopping habits, the report says, creating a generation of "robo shoppers" who research purchases in shops before buying online.
More than 50 per cent of smartphone owners said they used their phones to photograph products in shops, to check prices on comparison sites or to scan bar codes in shops.
It found that adults sent an average of 3.2 letters a month, with people claiming their use of the post had declined 30 per cent over the past two years.
Despite this, postal revenues increased 4.5 per cent to £6.7bn in 2011, partly on the back of rising postal prices in 2011 and a greater number of packages being sent through the post.
Ofcom said the post was benefiting from a rise in UK online retail sales, which rose 30 per cent to £2.6bn in the year to the end of February.
More News From Financial Times