The Commerce Commission has given Vodafone the green light to acquire management rights to the 890MHz and 900MHz spectrum it bought at the recent spectrum auction in July.
Vodafone engineering general manager Jeni Mundy said at the time the spectrum would be used to boost Vodafone's capacity, not for new services.
"One of the challenges in designing a network is re-using our frequencies, so buying new spectrum gives us more frequency, which will reduce the emphasis on frequency re-use and enable us to provide a better quality service."
The test for whether the purchase should go ahead is whether it would, or would be likely to, substantially lessen competition in the mobile telephony market.
Vodafone paid $2 million for the spectrum.