The Commerce Commission says Telecom should pay more than half the $50 million Telecommunications Development Levy for the 12 months to the end of June.
In its draft determination, the industry watchdog says Telecom's share should be $25.4 million, Vodafone should pay $11 million and Chorus $6.4 million.
In total, it proposes to levy 26 companies.
The levy is used to pay for non-commercial telecommunications infrastructure such as the relay service for the deaf and hearing-impaired, broadband for rural areas, and improvements to the 111 emergency service.
Telecommunications Commissioner Dr Stephen Gale says the levy amounts to about 1% of revenue.
He says it is paid by companies, or groups of companies, earning more than $10 million a year from operating part of the public telecommunications network, whether fixed or wireless.
Companies have until 5 June to lodge submissions.
