Bank of Queensland is lifting interest rates for housing investor loans by 0.25 of a percentage point, while owner-occupiers will wear a rate hike of about half this size.

In a surprise move blamed on higher funding costs, the regional lender on Thursday announced the first significant rate hike for mortgage customers since most banks raised interest rates in late 2015. It's a change that is likely to be watched closely by rivals.

BOQ also raised its interest rates by 0.18 of a percentage point independently of the Reserve Bank in November last year, a time when most banks were hiking rates.

Chief executive Jon Sutton made the announcement on Thursday as the bank announced a 7 per cent lift in first-half cash profit to $179 million, helped by faster loan growth and low bad debts.