IMB finished 2012 solidly after reporting an after-tax profit of $14.1 million for the six months to December 31.
The result was 6 per cent lower than the corresponding period in 2011 when the mutual building society reported a net profit of $15.1 million.
Chief executive Robert Ryan said IMB's balance sheet was maintained at $4.7 billion.
Despite a slight decrease in profits the result highlighted IMB's strengths and the way it had managed market trends and contracting interest margins, he said.
"We have had a number of interest rate cuts and still made a good profit."
Mr Ryan said the profit had been achieved during a slowing lending market, continued high-funding costs and moves by IMB to increase its capital levels before implementation of the international regulatory framework for financial institutions.
He said that was in line with the share buyback initiative that would continue incrementally, with the next opportunity in September.
"In terms of the industry I think we are still going along quite well ... and we are well placed to continue to grow," he said.
"We have continued to put staff on ... and will take on more trainees in the next few months."
Mr Ryan said the latest result showed IMB's capital ratio had increased by 1.9 per cent to 15.9 per cent against the corresponding period last year and its liquidity ratios remained well above prudential requirements.
During the past six months IMB had focused on investing in mobile and internet banking facilities and continued to improve member service and experience, he said.
IMB at present enjoys a member satisfaction rating of 96 per cent and a Roy Morgan Customer Satisfaction Monitor rated IMB members as the most satisfied of all building societies.
Looking ahead, Mr Ryan expects that the recent interest rate cuts would help stabilise the property market in 2013.
Chairman Michael Cole said IMB was well positioned to continue to grow and meet members' needs.