"While these rules do not apply until 2013, or in certain cases 2014, it is a positive sign that some service providers have already taken steps to introduce better consumer notifications about high usage."

Cohen also told a press conference the TIO has begun to receive some complaints about the NBN.

"We don't specifically report on complaints about infrastructure providers such as the NBN, but we have had a very small number of complaints about consumers who have been on NBN services," he said.

Overall, the largest number of complaints were recorded in NSW, with 60,398 complaints, followed by Victoria, with 56,785 complaints lodged in the state.

In 2011-12, the TIO carried out 79 systemic investigations.