Australia's second largest telco Optus is losing mobile customers and expects mobile revenue to continue falling over the next 12 months.
The company has also not ruled out more job cuts, as it removes 350 staff in May as part of changes aimed at improving profits.
Optus lost 160,000 mobile customers in its 2013/14 fiscal year, which ended on March 31, to 9.43 million.
Revenue from mobile phones and broadband dropped six per cent in that time, to $5.4 billion.
Optus expects mobile revenue to continue falling by a "low single digit" percentage in the 2014/15 fiscal year.
Interim chief executive Paul O'Sullivan said the drop in revenue was caused by a reduction in mobile termination rates and lower equipment sales.
"It also reflects our focus on customer experience where we took the decision in previous quarters to reduce excessive pricing for voice and data breakage and roaming," he said.
Despite lower revenue, the company's annual profit grew by 15 per cent to $835 million, due to lower costs.
"The full year results show we are making the necessary changes to restructure the Optus organisation so we can take advantage of future growth opportunities which will result in customers increasing demand for data," Mr O'Sullivan said.
The restructure has involved job losses, with average staff numbers falling by 267 in the year to March - before the 350 cuts to be made in May.
Mr O'Sullivan said the company had to cut costs to remain competitive.
"It's really important that we have an efficient company and that we are always optimising our cost structure," he said.
"That will be an ongoing process in the company forever."
Optus' parent company Singapore Telecommunications posted a four per cent rise in annual profit to $S3.65 billion.
Singtel's locally listed shares were down one cent at $3.26 at 1530 AEST.
