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How to Use Facebook Lookalike Audiences in 2021

Updated: Nov 17, 2021

Lookalike audiences used to be the go to targeting method for Facebook advertisers, but in the past year, the ios 14.5 update has made some changes to Facebook’s algorithm which have left businesses seeing worse results from Facebook’s ‘lookalike audiences’ feature in their ad campaigns.

However, you don’t have to give up hope of the success you expect from lookalike audiences just because of the new changes; all that’s needed is that you take a new approach.

This article will break down how to use lookalike audiences in your business’s Facebook advertising campaigns to get the best results in 2021.

What is a facebook lookalike audience?

To create a lookalike audience, Facebook’s algorithm takes a group of people (your ‘source’ audience) and closely matches those people to other, similar instagram or Facebook users. By finding users similar to those who have bought from your business in the past, Facebook can find you an audience to target which has great advertising prospects.

Historically, the best approach to creating a lookalike audience for your Facebook adverts has been to use a source audience of website visitors, filtered to people who actually made a purchase. This way, you would be targeting those most likely to meet your ideal outcome from your Facebook ad campaign.

Lookalike audiences are a very effective strategy to use in your Facebook advertising, so it’s worth learning how to use this method. Here is an in depth video on creating Facebook lookalike audiences:

But before watching, read on to make sure you are using the best techniques for 2021 after the ios 14.5 changes.

What are the changes to facebook lookalike audiences in 2021?

The issue that the ios 14.5 update has caused for those advertising to lookalike audiences in 2021 is that the new gdpr rules from apple have affected source audiences. Ios 14.5 has given Apple’s users more control over how their data is used, but this also includes the option to opt out of having their activity tracked by sites such as Facebook.

The problem with these new restrictions to tracking for Facebook advertisers is that Facebook’s algorithm can’t gather as much information as it used to about your source audience. If a lot less people who click the purchase button on your site can be recorded as doing that, then you’re not going to have much information on your source audience for Facebook to use to find a lookalike audience which is actually similar enough to translate into more purchases and a successful ad campaign.

What is a good size for your Facebook Lookalike audience?

The reduction in source audience size since the ios 14.5 updates has definitely reduced Facebook’s ability to create effective lookalike audiences. The relationship between source audience size and lookalike audience outcomes isn’t news. Even before the changes, if your business had a small number of purchases to create a source audience, and therefore a lookalike audience from, they would not get the same results as a business whose lookalike audience could be built from a source audience of thousands. This is because the more data you give Facebook to create a lookalike audience from, the more of an understanding its algorithm will have of your audience, and the more accurate its profiling of a lookalike audience will be.

So, now you know source audience size is important, what source audience should you be using?

Before ios 14.5, most businesses using Facebook lookalike audiences would have used website purchases as their source audience. But, as we have covered, this source audience is now going to be smaller because less data can be collected at this stage. The way to get more data for yoursource audience, and create effective lookalike audiences, is to create your source audience from a group further down the scale of interaction.

Purchases might be your ideal action for a customer to take, but a lot more people might add to basket, or even just visit the website, and this group is still a great indication of who is interested in your products, and what kind of other people it is worth targeting with your Facebook ads.

As with all Facebook ad strategies, it is worth testing things out, and trying a couple of source audiences to find what works for your business. This being said, the general advice on what to prioritise when choosing your source audience has changed in the past year, and this is worth bearing in mind as you choose what to test. Before 2021 it would generally be advised to go as close to your desired outcome as possible to find your source audience, and target those who actually purchased. The priority now for increasing lookalike performance is generally audience size, and targeting bigger audiences, even if further from your ideal audience, has greater success rates.

So what source audience should you be using for the best results in 2021?

So, overall, basing your lookalike audience on a larger source audience is now the priority over basing it on a source audience of people who actually purchased your product or service. With that in mind, the most common source audience people now use is website visitors, as this allows Facebook to create a lookalike audience based on people who were interested enough in your product to leave Facebook when they saw your ad.

There is also a way of creating a source audience using data from outside of Facebook, which can be a very strong strategy for building a lookalike audience in 2021. If you set the custom audience for your source audience to website visitors, there will be a limit on your data pool, because facebook can only ever use data from within the last 180 days due to GDPR. If you want an even larger data set, and one which covers a longer time period, a good strategy is to upload a customer list of people who have bought from your business in the past or perhaps who have added their details to an email list. This way, you can target a large source audience which isn’t limited by Facebook’s data restrictions.

The downside to using a customer list you have created for your source audience is that Facebook then has to match the names on your list to Facebook or Instagram profiles, which might not be possible for all of them. You will also have to keep your source audience up to date manually by uploading new customer lists, whereas when you use website visitors as your source audience, Facebook can update that information automatically.

So, website visitors or a customer list are both great options for source audiences in 2021, depending on your priorities. However, as a customer list is not limited to 180 days of data, this is usually the bigger data set, and therefore leads to the most well chosen and effective lookalike audiences for your ad campaigns.

If you don’t have a customer or contact list, you could also base your source audience on people who have viewed a video from your company or engaged with your content on Facebook or Instagram. These interactions are far enough up the scale of interaction we mentioned earlier to encompass a large group of people, which performs better since the ios 14.5 update. If you are basing your customer list on interactions with your Business’s online social media, it is best to stick to interactions on Instagram and Facebook as this means they are active on the platforms where facebook can gather information on them to use when creating your lookalike audience.

Overall, 2021 is the year that lookalike audiences with bigger source audiences to work from overtook lookalike audiences built on purchases and high investment interactions.

Keep your source audiences broad, and remember that Facebook is going through a real dip in their data after the ios 14.5 update, so the more data you can provide Facebook, the better Facebook can work for you to get your adverts performing better than ever despite the new changes.

To learn more about Paid Ads and how effective it can be for you, click on the link and you will be directed to our main page for more details.

If you would like to know more about how to use Facebook lookalike in 2021, contact Regal Roye today and we'll help you through it.

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