Email is the preferred way for ISPs to inform customers they are over their fair usage limits and could face extra charges, according to a new poll of UK broadband users.

In a new study from thinkbroadband.com, a warning email was cited as the favoured way of letting customers know by nearly three quarters (74 per cent) of respondents.

In second place, albeit trailing by 70 per cent, was messages in web pages with nine per cent of the total, followed by being informed by a letter which was favoured by six per cent.

Meanwhile, being informed by text message and telephone call polled five per cent and six per cent respectively, while three per cent said there was no need to be told by an ISP at all.

Commenting on the findings, thinkbroadband.com said: "Perhaps having multiple options available to the end user may be the best approach.

"The user could then choose what they feel is right for them, whether this be to implement a limit so no more data can be downloaded when they reach their usage limit, or one of a number of options for notification when you are approaching it."