TELSTRA is considering charging its customers a one-off, $1 charge to offset the effects of the carbon price.
APN Newsdesk has obtained a focus group letter in which the telco raises the prospect of introducing a "Network Electricity Surcharge".
Telstra argues, in the letter, the surcharge is necessary because its electricity prices have increased as a result of carbon pricing.
The letter will only be sent to customers if Telstra decides to impose the levy.
"The charge will apply to your home phone, mobile, and/or internet services," the focus group letter reads.
Telstra's website says its has 8.1 million fixed line and 13.8 million mobile services, including wholesale services, 2.4 million retail fixed broadband customers and more than 2.5 million mobile broadband customers.
Each service would attract the $1 levy.
Telstra is not included on the list of entities liable to pay the carbon tax.
But Opposition climate change spokesman Greg Hunt said such a charge would be "in line with the direction the government has given businesses, to pass through the cost to their customers".
"People are already in shock at the carbon tax increase on their gas and electricity bills which are currently arriving in letter boxes," Mr Hunt said.
"Now their phone and internet bills could be next. Telstra has confirmed it is testing the letter and if it decides to impose the extra charge, it will inform customers."
A spokeswoman for Climate Change Minister Greg Combet said the proposal was a "matter for Telstra".
While Telstra did not return APN's calls, a company spokesman did tell News Limited on Thursday it had made "no decisions about pricing changes", but did not rule out the fee.