The national vacancy rate remained well under 2% in March - indicating that tight rental market conditions continue.

SQM Research's latest figures place the overall vacancy rate at just 1.6%, the same rate as in March 2010, despite a softening housing market. The firm puts the ongoing low vacancy rates down to a hesitancy from buyers to leave the rental market due to high interest rates. This, in turn, is aiding in a greater demand for rental dwellings.

"As the housing market enters further into its downturn, more and more would-be buyers are waiting on the sidelines, hoping for more price falls," said SQM Research managing director Louis Christopher. "Indeed, there are now less first home buyers in the market than what we had ten years ago. Of course, these buyers still need somewhere to live, and so the demand for rental accommodation has accelerated in the past 18 months."

The city with the lowest vacancy rate in March was Canberra, at just 0.6%, followed by Perth at 0.9%, then Sydney and Adelaide at 1.2%. Melbourne and Darwin had the highest vacancy rates at 2.4% and 2% respectively. The only capital city to record an increase in vacancies was Hobart, which grew by 0.3%.