The levy was established in 2011 to pay for telecommunications infrastructure and services that are not commercially viable, including the relay service for the deaf and hearing-impaired, broadband for rural areas, and improvements to the 111 emergency service.
The commission is inviting submissions on its draft and expects to release its final decision in December.
Spark said in a statement that the draft decision was not unexpected as it was based annually on a revenue-share formula that the commission uses to determine how the cost is calculated.
"It's worth remembering that ultimately, the levy is paid by consumers through higher prices."
A Chorus spokesman said the company accepted the decision, which was largely in line with what it had expected.
Vodafone said in a statement the TDL had an important role to play in helping fund some of the more economically-challenging, community-focused telecommunications initiatives. It did not have anything further to add regarding the decision process currently underway.
A 2degrees spokeswoman said the company's increasing contribution to the TDL was a reflection of its growing market position.