New Zealand house sales have fallen 11 consecutive months, with fewer properties put up for sale in the lead-up to the general election and mortgage loan restrictions reducing activity at the lower end of the market.

The number of houses sold fell 12 per cent to 5,911 in September from the year earlier month, while sales of houses below $NZ400,000 declined 18 per cent, according to Real Estate Institute of New Zealand figures.

New Zealand’s Reserve Bank in October 2013 introduced restrictions on high-debt mortgage lending in an attempt to cool the housing market which is being driven by a shortage of housing in Auckland and earthquake devastated Christchurch.

However, activity did pick up in the last 10 days of September, following the general election on the 20th, the institute said.

“Despite stronger activity in the latter part of the month, sales volumes were again well down on the same time last year, meaning that sales volumes compared to last year have now fallen for 11 months in a row,” the institute’s chief executive Helen O’Sullivan said in a statement.

“A key theme reported by agents across the entire country is a lack of new listings. This may, in part, be a lag effect from the election – as with sales activity, listing interest is reported as having picked up in the last week of September.”

The median price gained five per cent in September to $NZ420,000 ($A391,007) from the year earlier month, the institute said.

In September, the time taken to sell a house rose by four days to 35, compared with September last year, although it took three days fewer than in August, according to the real estate industry figures.

The stratified median housing price index, a measure developed to smooth out peaks and troughs in the market, increased 4.1 per cent from September 2013 and was up 0.2 per cent from August.

Auckland prices rose an annual 7.7 per cent, while Christchurch increased 7.1 per cent and Wellington 1.7 per cent, according to that measure.