The tariff enables groups of four or six people to call each other for free at any time, providing they are all Vodafone customers.
The £5 a month option allows a customer to make free calls with three chosen people, while for £7 the customer can nominate five people.
"Vodafone's dedication to adapting to customers' specific needs, while providing the best value, is more evident than ever with this new initiative," said Tim Yates, director of Vodafone's Consumer Business Unit.
"We all have very pressured lives, juggling family, friends and work, and this tariff will ensure that we can always stay in touch."
The tariff can be added to any existing price plan, enabling all Vodafone customers to take advantage of the offer.
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