The new SIM-only dongle deal from 3 is UK’s most flexible and cheapest mobile broadband tariff, the broadband provider claims.

Under the terms of 3’s offer, consumers pay just £15 for 5gb of usage per month. This is enough for 5,000 emails or about 50 hours of web surfing, with customers free to cancel at any time with only 30 days notice.

Consumers who already own a 3 dongle can simply insert the SIM card to take advantage of the deal. The SIM can also be placed into a broadband-embedded laptop. Alternatively, mobile broadband novices can buy a Huawei MF627, E156g and E15 USB modem from 3 for a one-off charge of just £19.99 and then sign up for the package.

According to 3, the data allowance provided by the offer is a full 2GB more than similarly priced deals from other broadband providers. The usage terms also compare very well with currently available pay as you go mobile broadband offers.

Jessica McArdle, marketing manager of Top 10 Broadband, said: “At just £15 per month, these new deals from 3 once again break new ground in the mobile broadband market.

“Following on from the success of their 15GB usage plans, 3 has introduced a great option for consumers who do not want to get tied down to a lengthy contract.”

News of the broadband supplier’s groundbreaking deal comes after the company recently announced it has sold over one million USB modems. Demand for its services is thought to have been driven in part by astute marketing campaigns that targeted struggling consumers who are concerned about accruing punitive charges for exceeding their usage limits.

The firm is currently closely involved with the government’s Digital Britain project, which aims to deliver a 2Mb broadband connection to every household by 2012. At the start of June, 3 was engaged in negotiations to persuade Vodafone and O2 to sell off spectrum that will become available when analogue receivers are switched off.