Retargeting with ads: What is it and how does it work?

Learn how to engage your web visitors with retargeting even after they leave your site, to eventually secure a purchase.

We have all been there before. One moment you are browsing for shoes on an online store, and over the next few days, all you see are ads of the very same shoes you were looking at, as well as others that the store has. This is retargeting - the practice of serving ads to visitors after they leave your site. It’s one of the most effective ways of keeping your product in the mind of your potential customer and trying to secure a purchase.

Why retarget your web visitors?

The best and simplest reason is that most customers may be just browsing when they visit your website and is not ready to make a purchase decision yet. By retargeting them with ads or even promotional content, the customer is reminded or incentivised to return and make a purchase.

How it works

Retargeting works by placing cookies in the web browser when someone visits your site, which acts like an anonymous and invisible online tracking device. Cookies tell advertising platforms whether a customer has interacted with your website but does so without sharing the personal information of that customer.

After visitors leave your site and browse websites of the retargeting platform’s partners, the cookie will be detected and relevant ads will be served or displayed to the user. For instance, if you choose to do retargeting through Google’s banner display network, your ads will be shown on the pages of Google’s partner websites.

Choosing the right platform

There are a few different platforms you can choose from to place retargeting ads. Aside from Google Display Network and Facebook, there are other platforms such as third-party agents that help you secure ad spaces on partner sites to display your ad on sites that your visitors frequent. Each platform has its unique pros and cons and will work differently based on your marketing needs.

Customising your campaign

Before you start your campaign, here are some factors you need to consider:

  • Who are you targeting?
  • Which are the sites that your potential customers frequent?
  • How do you want to be charged for your campaign? There are generally three options. Cost-per-click (CPC) means you’re charged when someone clicks on your ad. Cost-per-mille (CPM) is when you’re charged every time your ad appears 1000 times across the partner websites. Cost-per-acquisition (CPA) is when you’re charged when you convert a customer from the ad.
  • How will you measure success? Do you want to drive sales or enquires from a specific landing page? Is it a brand recognition campaign?

With these in mind, you can pick a suitable platform for your marketing needs and customise your campaign to drive the best results.

Avoid spamming

Although technology has given us the ability to retarget potential customers on sites and platforms they frequent, this does not mean that we should spam them with ads all the time! Be clear on the objectives you need to achieve with your campaign, and selective on the audience you want to target. This will ensure that you get the right customers, and you don’t end up putting them off your business instead.

A/B Testing

As with all ads, the best practice is to conduct A/B testing on different ad formats and platforms. Try different iterations of ad sizes, text copy, calls-to-action, and track which sites bring you the best results— be it reach, clicks, or conversions. Ensure that you include a unique UTM link for every ad to track your campaign.



  • Retargeting allows business to keep serving ads to customers after they’ve left the business website
  • It’s an effective way to still interact with customers if they didn’t complete a purchase
  • There are many different retargeting platforms – pick the one that helps you achieve your marketing objectives
  • Customise your campaign to achieve specific marketing goals
  • Avoid spamming users with your ads on every site they visit
  • A/B test different ad formats and platforms to find the right campaign for your business