Set Up Campaigns for Lookalike Audiences

What Exactly is a Lookalike Audience?

A lookalike audience is a targeting tool that lets ad platforms find new people who closely resemble an existing group of customers or leads.

You provide a source audience — your customer list, a list of past purchasers, or people who completed a lead form — and the platform analyses the patterns in that data to identify other users who share the same characteristics.

On Meta, this analysis draws on thousands of behavioural signals: what people engage with, what they buy, how they browse, and what they respond to. On Google, it works similarly through Google’s audience data and the intent signals it observes across Search, YouTube, and Display.

The quality of a lookalike audience depends almost entirely on the quality of its source. A lookalike built from a small or broad list will underperform. A lookalike built from your highest-value customers — people who bought at full price, booked an appointment, or completed a specific action — will produce a more qualified pool of new prospects.

 

How the Setup Works

Step 1 — Your existing customer data and ad account performance are reviewed to identify the best source for your lookalike audience. This is usually a customer list, a pixel-based audience of purchasers or leads, or a CRM export.

Step 2 — The source audience is cleaned, prepared, and uploaded or connected to the ad platform in the correct format. For Meta, this means uploading a matched customer list or linking a custom audience from your pixel data.

Step 3 — Lookalike audiences are created at different similarity thresholds — typically one percent for the tightest match and broader percentages for scaled reach. Each percentage represents how closely the new audience resembles your source.

Step 4 — Campaigns are built specifically for the lookalike audiences, with creative and messaging matched to a cold audience that does not yet know your brand.

Step 5 — Tracking is confirmed so that conversions from lookalike campaigns are measured separately from your retargeting or warm-audience campaigns, giving you clean data on performance.

Step 6 — The campaigns are reviewed after the initial learning phase and adjusted based on early performance data.

 

Why Lookalike Audiences Produce Better Results

Interest-based and demographic targeting asks you to guess who your customers are. You choose categories, age ranges, or behaviours that you think describe your audience — but you are estimating.

Lookalike targeting starts from a different position. It works backwards from people who have already done what you want new customers to do. The ad platform does not guess. It analyses real behaviour from your actual customers and finds patterns that human targeting cannot replicate.

This matters for cost. Campaigns targeting cold audiences built from guesswork typically pay more per lead or sale because the audience quality is inconsistent. Lookalike audiences narrow the pool to people the platform has identified as genuinely similar to your buyers — which typically produces a higher conversion rate and a lower cost per acquisition over time.

It also matters for scale. Interest-based audiences have a ceiling. Lookalike audiences are refreshed automatically as the platform continues to observe new people who match the profile, which means your reach grows alongside your business.

 

Why Interest Targeting Alone Is Leaving Results on the Table

Most businesses running ads rely primarily on interest and demographic targeting. This works well enough in the early stages when there is no customer data to draw from.

But over time, as a business collects customers, runs a CRM, and accumulates pixel data, the most valuable targeting asset is no longer a list of interests — it is the pattern of behaviour in your actual customer base.

Businesses that continue to rely only on interest targeting while this data sits unused are funding campaigns based on approximations when they have the information to do much better.

The gap shows up in cost-per-lead figures that plateau or creep upward, audiences that fatigue quickly, and campaigns that produce volume but inconsistent quality. Lookalike audiences address all three by grounding targeting in demonstrated customer behaviour rather than assumed identity.

 

What We Will Do During Your Lookalike Audience Campaign Setup

• Review your current ad account and customer data to identify the best source for your lookalike audiences
• Prepare and upload your source audience in the correct format for Meta or Google
• Build custom audiences from your pixel data, customer list, or CRM export as the foundation for the lookalike
• Create lookalike audiences at the appropriate similarity percentages for your market size and goals
• Build campaigns specifically structured for cold lookalike targeting, with appropriate creative direction and messaging
• Confirm conversion tracking is in place so lookalike performance is measured cleanly
• Set up the initial campaign structure ready for launch and provide a brief overview of what to expect during the learning phase

 

You Need Lookalike Audience Campaigns When

• Your current campaigns are performing and you want to reach more of the right people without starting from scratch
• You have a customer list, CRM data, or pixel-based audience large enough to build a reliable source
• Your cost per lead or cost per acquisition has been increasing and you want a more targeted approach to cold audiences
• You are running Meta or Google ads but relying solely on interest or demographic targeting
• You are scaling your ad spend and want to ensure the broader audience you reach is still qualified

 

What We Need From You to Set Up Lookalike Campaigns

To build and launch your lookalike audience campaigns, the following is required.

• Admin access to your Meta Business Manager or Google Ads account
• Your customer list in CSV format, or confirmation that your pixel or CRM is connected to the ad platform
• Confirmation of your primary conversion goal — purchases, leads, bookings, or calls
• Access to any existing campaign data so we can review what is already working
• Your website URL and, if relevant, the specific landing pages your ads will drive traffic to

If your customer list is small or your pixel data is limited, this can be discussed before work begins to agree on the best available source.

 

When You Should Set Up Lookalike Campaigns

Lookalike campaigns are most effective once you have a meaningful volume of customer data to draw from. On Meta, the recommended minimum is a few hundred matched customers for a one-percent lookalike — though more data almost always produces a stronger result.

If you are still in the early stages and your pixel has limited data, the priority should be to build that foundation first through conversion-optimised campaigns before layering in lookalike targeting.

For businesses that have been running for a year or more and have an existing customer base, this is a task that should already be in place. The data exists. Using it is simply a matter of setting up the audiences and campaigns correctly.

If you are scaling ad spend, this is one of the highest-leverage steps you can take before increasing budget. Spending more on a well-structured lookalike campaign produces better returns than increasing spend on the same interest audiences you have been running.

 

Frequently Asked Questions

How many customers do I need to build a lookalike audience? Meta recommends at least 100 matched users in a source audience, though performance improves significantly with more data. A source of 500 to 1,000 matched customers will produce a far more reliable lookalike than a list of 100. If your customer list is small, a pixel-based audience of people who completed a conversion event can serve as the source instead.

Should I use one lookalike percentage or multiple? It depends on your goals and market size. A one-percent lookalike is the tightest match and is the best starting point for most businesses. Broader percentages — two to five percent — can be used to increase reach, but the similarity decreases as the percentage rises. The right structure depends on your budget and how quickly you want to scale.

Can I use this on both Meta and Google? Yes. Both platforms support lookalike-style targeting, though the tools are named differently. Meta calls them Lookalike Audiences. Google refers to them as Similar Segments, available for Display and YouTube campaigns. The underlying logic is the same: both platforms find new users who resemble your existing customers. The setup approach differs depending on which platform you are using.

 

Want Your Lookalike Campaigns Set Up Correctly?

Building lookalike audiences that actually perform requires the right source data, the right audience structure, and campaigns built specifically for cold audiences — not repurposed from your retargeting or warm-traffic campaigns.

At 10x Marketing Lab, the setup is handled end-to-end: from reviewing your customer data and pixel setup, to building the source audiences, creating the lookalikes, and launching campaigns structured for cold audience performance.

You receive a properly configured setup with clean tracking in place, so you can see exactly how your lookalike campaigns are performing from the start.