While one-third use the devices at dinner, presumably for texting and not talking.
Research from Lloyds TSB shows the handbook of phone manners has been thrown out of the window. Over half of UK phone users talk on the device when in bed, while 34 per cent use their phones at dinner.
Mobiles even seem too irresistible during calls of nature with 24 per cent admitting they've used their phone in a public toilet.
Additionally, three-quarters use their phone in the street, 63 per cent use them on public transport, while 12 per cent have used their phone in a meeting or during a presentation.
Results also show 11 per cent have used their phone at a theatre, cinema or concert, which rises to 29 per cent for under-25 year olds. Nine per cent have even used their phone during a wedding or christening.
However, all isn't lost as 70 per cent still consider it unacceptable to use a phone at the theatre, cinema or concert hall. Worryingly, that figure falls to 51 per cent for people considering it inappropriate during dinner at a restaurant, falling further still to 21 per cent against use in a public toilet.
Ashley Machin, director of digital banking at Lloyds TSB said: "This research shows how quickly mobile phones are becoming the most versatile and important gadget in peoples' lives."