TelstraClear has posted an operating loss of $5 million before interest and taxation.
That compares with a $16m same-basis profit last year.
Chief executive Allan Freeth said it had been a pleasing result in a difficult year, marred by natural disasters and "continuing global economic woes".
Revenue for the year to June was up 1.2 per cent at $701m.
TelstraClear has a cable network and customer care centre in Christchurch, and said the earthquakes had taken up a good deal of the company's time and attention.
"We were still able to deliver year-on-year national revenue growth in the business and government, consumer, and wholesale segments," he said.
Operating expenses increased by 5.4 per cent, largely because of the earthquakes
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