O2 has increased its paid paternity leave package to 14 weeks for all permanent employees, including workers in its high street shops.
Prospective fathers are only entitled to a minimum of two weeks paid leave under existing law.
The extended paternity policy, which is being introduced on Monday, will cover heterosexual and same-sex couples, as well as adoptive and surrogate partners.
It covers employees in retail as well as office roles, making it one of the best parental leave policies in the retail sector.
Speaking to the Press Association, O2’s chief HR officer Ann Pickering said she had noticed other retailers restricting offers to head office.
“I’ve seen other organisations have been selective about where they’ve applied it,” she said.
“I would never dream of implementing a policy that only applied to head office, that’s very divisive. It’s really important to give new parents a chance to spend time with their child.”
According to a report published last year by Incomes Data Research, just 9% of employers offer more than the statutory two weeks for new fathers.
Ms Pickering said the new policy was part of a wider mission at O2 to offer flexible working options, to encourage a “more diverse, balanced and inclusive culture”.
It comes as retailers report their gender pay gaps ahead of the deadline later this week.
Telefonica UK, the company that trades as O2, has a mean gender pay gap of 17.3%. This is primarily down to a higher proportion of women being employed in the lowest-earning jobs.
Ms Pickering said that although the enhanced paternity package would not affect the gender pay gap, it was part of wider efforts to make the company an attractive place to work.