ISPs could face counting the pennies if the popularity of mobile broadband - using a dongle or data card on your laptop or PC - continues to rise.
According to the latest survey by YouGov Mobile Broadband could actually pose a serious threat to traditional internet service providers.
The YouGov research team found that around one in eight mobile broadband users have either replaced their fixed line ISP or chosen a mobile broadband service in preference to a fixed ISP service.
It writes: "With increasing numbers of households dispensing with their landlines (13% according to Ofcom) accessing the Internet through the mobile phone network is a viable option especially for the young and mobile".
And there's more bad news for ISPs for the future with a further 5% of people that are currently running both mobile broadband and a fixed ISP service relating that they are intending to cancel their ISP service in the next 12 months.
However, adds YouGov, the providers of mobile broadband services need to step up their services.
The research revealed that more than a quarter of existing mobile broadband customers can be considered unlikely to renew their mobile broadband contracts or to continue to use mobile broadband on a pre-paid basis.
The main problems seem to be connection speed and expenses.
Commenting on the results, Marek Vaygelt, head of technology and telecommunications consulting at YouGov explains: "Customers find Mobile Broadband easy to use and install but transmission speeds and to a lesser extent network coverage reduce the initial enjoyment of getting up and running".
"It is in these areas that fixed ISPs have a distinct advantage and need to concentrate their marketing effort to minimise customer loss."
YouGov's DongleTrack Report was based on interviews with 1050 mobile broadband users and 2050 non-users in the UK.