Retailers who do not plan ahead may find themselves missing out on valuable traffic this Christmas, Google said.

Based on traffic patterns for past Christmases, over the next five weeks shopping-related search traffic is expected to accelerate dramatically as Australians wrap up their online Christmas research and start heading into stores or placing orders via the web.

According to Google, searches for "Christmas" specific questions so far this year are up year-over-year in all major retail categories; this year’s big winners include mass merchant retailers (searches up 47%), food and drink (+31%), and toys (+28%).

Ross McDonald, head of retail, Google Australia, said retailers should aim to anticipate when their customers will be searching for gifts or looking for stores and adjust their online advertising budget and message accordingly.

“Businesses need to take a strategic and long term approach to their online Christmas campaign,” he said.

“Last year, we saw some major retail advertisers miss 80 per cent of their potential search traffic because their daily ad budgets were the same as the middle of the year. That’s like forgetting to put your most popular product out on shelves during the busiest season of the year.”

Google has also found that smartphone shopping are increasingly being used as key tools. It is expected in the two weeks before Christmas, shoppers begin using their smartphones to search for brick-and-mortar stores. Already, over 30 per cent of such searches come from mobile with expectations that the number will rise further during the last 14 days.