Sprint, the third-largest mobile operator in the US, launched a range of so-called “framily” plans. They allow up to 10 family members or friends to sign up to Sprint services as a group. And the more people in the group the greater the savings.

For one line of service, new Sprint customers pay $55 per month per line for unlimited talk, text and 1GB of data.

But under the “framily” scheme, the cost per person goes down $5 a month for each additional new Sprint customer that joins the group. There is maximum monthly discount of $30 per line.

So, build a group of at least seven people, said Sprint, and everyone gets unlimited talk, text and 1GB of data for $25 per month per line.

Family plans have become increasingly popular in the US. And a benefit for operators is it’s easier to ‘lock in’ customers when they are part of a group as opposed to when they have individual plans.

However, Sprint has extended the concept by letting friends and neighbours join up, and each with separate bills. There is no sharing of data as in traditional family plans.

They become available on 10 January.

“The Sprint Framily Plan redefines the way we think of family plans and gives our customers the power to decide who will be a part of their group and gain greater savings as more members are added,” said Dan Hesse, Sprint CEO.

At an investor conference on the sidelines of the CES show in Las Vegas, covered by Reuters, Hesse conceded the new plans would squeeze ARPU but claimed the longer-term picture was rosier since churn rates would be lowered.

Moreover, because each customer is required to pay for his own mobile device – either through a one-time payment or by instalments – Hesse added that money would be saved on subsidies

Sprint’s “framily” deal is the latest in a series of aggressive marketing moves in the US mobile market.

Only days earlier, AT&T dangled carrots in front of T-Mobile US customers worth up to $450 to try and persuade them to switch networks.

T-Mobile US, the country’s fourth-largest operator, has cranked up the pressure on rivals in recent months with various price cuts and new incentives under John Legere, the firm’s ebullient CEO.

Sprint, now majority-owned by Japan’s SoftBank, has high ambitions for 2014.

Largely on the back of Spark rollout – Sprint’s “superfast network” combining 800MHz, 1.9GHz and 2.5GHz frequencies and an LTE overlay in metro markets – CTO Stephen Bye, speaking at the CES event, claimed the company was turning a corner.

“Clearly we’ve come a long way from where we were,” he said, but claimed also that “this year we will be able to say we are back in the game”.