Comparison Shopping Engines (CSEs) have been present on the net for nearly 10 years and allow consumers to look for, compare and buy products at the best possible prices.

Dealing with these CSEs, which have various functions and different business models, can quickly become an overwhelming task. Here are a few tips on the best ways to choose a comparison shopping site on which to reference your products.

How CSEs Work

A comparison shopping site is a service which allows consumers to compare the prices of several products on the Internet.

Comparison shopping sites index products, which have been sent through by retailers, in order to display listings of the best prices of each product sought by a consumer.

CSEs generally benefit from substantial traffic, notably due to developed natural indexing which ensures a better visibility of merchants’ products. Thanks to this exposure, listing on comparison shopping sites has become an essential strategy for online retailers.

In order to distribute your products on CSEs, you must send them through your product catalogue, generally in CSV, TXT or XML format. The catalogue will then be automatically integrated by the CSE on a daily basis. Once the feed has been submitted, the retailer’s job is done.

In order for your product information to stand out as much as possible, it is important to include all basic information in your product catalogue: Title, Category, Price, Shipping costs, Image, URL and Availability.

For some categories, it is also necessary to add the EAN or MPN codes of your products. This type of information can be very important – the more information you include on your products, the more online shoppers will be interested in buying them.

The Different Business Models

There are currently 3 different business models which exist for CSEs, the most common of which is the PPC model (pay per click).

PPC – Pay per Click

PPC is the most popular business model today and is used by the majority of comparison shopping sites. It is a relatively simple model, where the retailer pays for each click carried out on the comparison shopping site which then redirects the consumer to your online shop.

For example, if an online shopper clicks on a product on a CSE and is then redirected to the retailer’s website, the retailer will pay £0.16 for instance, whether or not a purchase is made.

The average CPC (cost per click) which we have noticed is £0.19. This rate may vary depending on the product category. The cost tends to be higher for High-Tech products or holiday packages, for instance, than for niche markets such as electrical fans.

This CPC may seem high, but it is much lower than that of other e-marketing channels, such as sponsored links. If their campaigns are managed correctly, CSEs can become very profitable channels for online retailers.

CPA – Cost per Acquisition

There is also another model, derived from the one often used by most affiliate networks: CPA (percentage of turnover generated).

Each time a shopper visits an online retailer’s website from a comparison shopping site and then makes a purchase, a percentage of the turnover is given to the CSE.

This model has the advantage of being relatively risk-free for retailers, as they only pay the comparison shopping site if a sale is generated.


The recent launch of a new free CSE has been extremely successful.

Google has put itself back on the CSE market with the launch of Google Shopping (or Google Product Search).
The advantage of this new comparison shopping site is that it is completely free for retailers. You can distribute your product catalogue without any costs involved.

How to choose the right CSE for your products

There are many comparison shopping sites in every country around the world, and it is important to carefully select the ones you would like to target. Here are a few criteria to take into account.


It is essential to set your monthly CSE budget per channel, as this budget can vary from one comparison shopping site to another. Big CSEs attract a lot of traffic and can thereby generate a significant number of clicks. As these clicks have a cost, the monthly budget can rapidly increase relative to the traffic.


There are general comparison shopping sites where you can distribute any type of product without any worries, but there are also specialized CSEs as well.

These sites are specialized in a particular sector and have developed significantly in the past few years. They can be interesting to use for certain types of retailers.

It is therefore necessary to target these specialized CSEs so as to avoid selling your “fashion & beauty” products sites specialized in “gardening & DIY.”

The Importance of Optimization

Each comparison shopping site has its own algorithm, its own Quality Score which is important to know and to assimilate in order to index your products correctly.

As it is the case for SEO or SEM, it is essential to optimize your product information content correctly in order to stand out on each CSE.

Each product must have as much detailed information as possible to make it stand out: the availability, the shipping costs, the title, the photo and finally the price must be as accurate and reliable as possible.

Always Measure Your Profitability

It is essential to measure your ROI when distributing your products on comparison shopping sites. Like all PPC models, managing your budget and tracking your ROI is the only guarantee of a successful campaign.

Each retailer has his own way of calculating his ROI in relation to different factors.
It is essential to follow your campaigns carefully in order to identify the channels, categories or even the products which may impact your total profitability.

A daily automatic or manual follow-up is important in order to be able to deactivate products which have a poor conversion rate or profitability, if necessary.
This will allow you to save money and even make additional profit each month. Why leave products which will never sell on a comparison shopping site if they are costing you hundreds of Pounds in terms of clicks?


CSEs represent a sizeable channel which enables you to reach a wide audience. With effective optimization and traffic follow-up, you can take advantage of an important and profitable distribution channel!