The Swedish-Finnish company posted a net profit of 18.34 billion kronor (2.07 billion euros, $2.71 billion) for the full-year, compared with 21.25 billion in 2010.
For the fourth quarter, TeliaSonera registered a net profit of 4.9 billion kronor, compared with 5.3 billion in the same period a year earlier, a drop of 6.3 percent which was in line with market expectations.
Sales dipped slightly in 2011, by two percent to 104.3 billion, but inched up by one percent in the fourth quarter to 27.1 billion.
The fourth quarter earnings were pretty much in line with forecasts by analysts questioned by DowJones Newswires, who expected sales of 26.9 billion and a net profit of 5.1 billion.
TeliaSonera said the number of customers rose by 5.7 million in the fourth quarter to 170 million.
"We have taken the technology leadership in many of our countries by being the first operator to launch 4G services," chief executive Lars Nyberg said in a statement.
After the launch of 4G services for tablets before Christmas, the company said it would offer 4G services for handsets in the first quarter.
Analyst Kimmo Stenvall at Finnish bank Pohjola told DowJones Newswires the fourth quarter report contained "few major surprises and was much in line with views," adding that mobile services "contributed quite nicely to the result."
The TeliaSonera share was down 1.23 percent in early afternoon trading on a
flat Stockholm stock exchange.