Bidding wars are breaking out because the number of homes going on the market in Waterloo region is at "historic low levels," local realtors say.

Housing prices continue to rise even though the number of sales has slowed, said Kitchener-Waterloo Association of Realtors president Tony Schmidt.

"We continue to see multiple offers on properties putting upward pressure on prices," he said in a news release with January's sale numbers.

In terms of sales, if you don't count the past two years where the market was hot, Schmidt said it was "a very typical January."

The follow are sales figures compared to those in January 2017:

149 detached homes were sold last month, down from 194.

70 condo units, down from 79.

27 semi-detached homes, down from 32.

22 freehold townhouses, up from 20.

The average sale price of all residential properties in January rose nine per cent to $458,750, compared to January 2017, when the average sale price was $421,104.

Schmidt noted tougher mortgage rules came into play on Jan. 1 this year, which has "sidelined some homebuyers."

But the rise in prices is largely due to so few homes going up for sale.

"The reality is we're still experiencing more demand than supply right now," Schmidt said.