New subscribers to BT's Business Total Broadband package will be given a mobile broadband bonus.
The telecoms giant is including free mobile broadband and dongle with the deal, which is also open to customers renewing their contracts.
That means for £27 per month, firms will receive ADSL broadband connection, mobile broadband and Wi-Fi in one business-friendly bundle.
BT's wireless broadband director David Hughes told PC Pro that the range of services would ensure that companies had online access for every occasion.
He said: "We're adding value to our broadband offer at a time when businesses are up against it on costs. It allows them to stay connected most of the time."
Meanwhile, BT is marking Small Business Week by handing a £10,000 grant to one lucky entrepreneur, as chosen by a panel of judges.