The bank says the average amount by which Brits overestimate their balance is £70.73, with Londoners being the most out of touch overestimating their balances by an average of £91.62.
But 84% of mobile phone banking users have a more accurate idea of their finances, with almost half of this group stating that since using mobile banking, they've become more aware of the value of their bank account.
The average bank customer checks their balance approximately four times a month, currently favouring the internet to do so. Financial curiosity peaks towards the end of the week with 9.49am on a Thursday morning the most popular time for bank balances to be checked.
Sean Gilchrist, Barclays digital banking director, said: "Being in control of your money starts with knowing how much you've got and where it is being spent. Online and telephone banking made that easier and now mobile phone banking is taking it a step further.
"Mobile phone banking is still a relatively new way of doing your banking but the number of users is growing at a phenomenal rate and simultaneously more features and functionality are being added. It's really encouraging to see the positive impact it is having on helping people stay in control of their finances in a quick, easy and convenient way."
