The National Party has proposed boosting the funding available to improve rural broadband by $150 million.
The money would come from extending the $50m annual Telecommunications Development Levy on telecommunications retailers such as Spark, Vodafone and 2degrees by a further three years until 2019.
The levy was established in 2011 to raise $300m, of which $285m has been earmarked to subsidise the rollout of faster copper broadband and fixed-wireless broadband to the 25 per cent of the population outside the footprint of the Government-backed ultrafast broadband initiative.
Many phone companies objected to the levy when it was proposed, arguing that the funds should come from general taxation.
Communications Minister Amy Adams said the extra $150m would pay for a $100m contestable fund open to communities that wanted to bid for funding to improve their fixed-line broadband, as well as a $50m fund to extend mobile coverage in more remote regions and to fill "black spots" on main highways and tourist areas.
Spark spokesman Andrew Pirie said the company did not comment on party policies, but the levy was introduced with a clear commitment that it would fall to $10m a year from 2016.