Vodafone has extended the availability of its U.K. LTE service to include prepaid customers.

The telco commercially launched 4G services this time last year and as of the end of June had signed up 1 million customers to its LTE network.

Now it aims to grow that subscriber base by adding a range of LTE tariff options for prepaid customers.

Packages start at £20 per month, for which users get 2 GB of data as well as 500 voice minutes and unlimited texts. Customers choosing this package or a more expensive option get unlimited data for the first month to help them decide what pricing plan will suit them best.

"Over the past year we've already signed up well over a million pay monthly customers to our 4G service and are now opening up this great opportunity to our pay as you go customers," said Cindy Rose, consumer director at Vodafone UK, in a statement.

"We're also offering the best value 4G smartphone available today and with great value Freedom Freebees [tariff plans] to go with it, now is the time to take 4G to pay as you go," she added.

Prepaid customers can choose from a range of smartphones, including Vodafone's own-branded Smart 4 turbo and Smart 4 power devices.

Rival operator O2 also marked the first anniversary of its U.K. 4G launch, although unlike Vodafone it shied away from revealing how many customers it has signed up.

O2 said customer uptake on 4G was double the level it experienced when it brought 3G to market almost a decade ago, but did not get any more specific than that.

In the past year O2 has carried 5,400 terabytes of 4G data; 20% of all data usage on its network is 4G, it said.

Meanwhile, clearly mindful that its major rivals are celebrating their 4G birthdays, EE on Thursday announced that its LTE network now covers 75% of the U.K. population.

EE launched its 4G network 10 months earlier than Vodafone and O2. By the end of June it had 4.2 million customers.