Online shoppers using price comparison websites (PCWs) are often unaware that the majority aren’t presenting a full picture of available products available, according to online search engine Pricesearcher.

Pricesearcher surveyed 2,000 UK consumers and found although 62% of online shoppers use PCWs to find the cheapest deals possible, 39% are unaware most PCWs do not show all the available options in the market due to retailer costs in listing all of their products.

This follows an investigation by the Competition and Markets Authority (CMA) examining digital comparison tools on PCWs, such as uSwitch and MoneySuperMarket, which compile lists of products and services in which consumers can view and make their choices.

The CMA concluded last month a set out guidelines for all PCWs, including displaying important and accurate information on product and services and communicating to consumers of protecting personal data and how they can use it.

Online shoppers generally visit four PCWs a time when researching a product or service, according to the latest research, with 59% more likely to make a purchase if they can view all the available options through one platform.

“We know UK shoppers have a keen eye for a bargain – but it’s hard for them to gather the information they need when shopping for a deal online when there are so many online sellers out there,” commented Samuel Dean, CEO and founder at Pricesearcher.

“At present, consumers are only being shown the options of products that retailers are willing to pay for.” he added.

Earlier in the year in the midst of the CMA’s investigation, Tradedoubler’s regional director, Dan Cohen, commented, “Many people don’t realise these websites are commercial organisations that spend millions of pounds on branding activities, such as TV advertising, which they have to make money to fund.”

In response to the CMA’s decision that PCAs aren’t required to give a “full market overview”, Cohen added that the sites need to become “more transparent, either telling consumers upfront that they are not showing deals from the entire market, or provide a full market review that includes the deals they don’t make a commission on.”