Match Rate & Customer Acquisition

One of the biggest reasons media buyers struggle to align with business profitability? Match rate.

Yet few marketers truly understand its impact—or even how to measure it.

If you're spending money on "customer acquisition" but can't reliably identify existing customers on platforms like Meta, you're likely burning serious ad spend and inflating your Customer Acquisition Cost (CAC) without realizing it.

Let’s break this down.

What is Match Rate in Digital Advertising?

Match rate is the percentage of customers you can accurately map from your CRM or first-party data to users on your ad platform (e.g., Meta, Google, TikTok). If you have 100,000 customers and Meta can only identify 20,000 of them, your match rate is 20%.

And that's a problem.

Without a healthy match rate, you can't trust your prospecting campaigns. You’re often targeting users you’ve already acquired, even if you’ve "excluded" your customer audiences.

Example: Hidden CAC Inflation

A common issue we uncover when auditing new accounts is high CAC, despite best efforts to exclude existing customers from prospecting campaigns. The cause? A low match rate. Meta simply doesn’t recognize a huge portion of your existing customers, so they get lumped back into your acquisition campaigns.

No, your "exclusion audiences" aren’t enough.

Why Match Rate is Hard to Measure

Thanks to recent privacy updates (think iOS14+), platforms like Meta no longer surface reliable match rate data. The closest thing you’ll find is the EMQ Score (Event Match Quality), a vague proxy that fails to show what percentage of your custom audiences actually match.

So, how do you measure match rate health?

Here’s a simple but powerful framework to get real visibility into your customer targeting accuracy.

Step-by-Step: How to Diagnose and Improve Your Match Rate

1. Set Up New Customer (NC) Tracking

Use a third-party server-side tracking vendor (like Blotout) to create a "New Customer Purchase" event. Sync this event to Meta via Conversions API.

2. Customize Your Reporting in Meta Ads Manager

Add a custom metric column for your New Customer Purchase event.

Then, create a second custom metric:
% NC Purchases = NC Purchases / Total Purchases

This instantly shows you the true percentage of net new customers being driven by each campaign.

3. Analyze Prospecting Campaigns

Look at your acquisition campaigns and measure what % of purchases are actually from new customers. In many cases, you’ll be shocked (and not in a good way).

If your NC Purchase % is low, your campaigns are cannibalizing your existing customer base.

The Fix: Shopify Audiences + Smarter Exclusions

If you’re on Shopify and eligible for Shopify Audiences, you have a powerful solution at your fingertips.

How to Implement the Shopify Fix:

1. Sync the "Existing Customer Plus" segment from Shopify Audiences to Meta.

2. In Meta Ad Settings, add this audience to your "Existing Customers" definition along with your pixel-based and Klaviyo-based purchase audiences.

3. Apply this enhanced exclusion to your prospecting campaigns.

What Happens Next?

• Your NC Purchase % jumps closer to 100%

• Your CAC drops

• Your media buying finally aligns with your P&L goals

Final Thoughts

Match rate isn’t just a technical detail—it’s a strategic lever. Poor match rates create a data illusion, making marketers think they’re acquiring customers when they’re just re-acquiring them.

By implementing accurate tracking and better exclusions, you unlock true customer acquisition and eliminate wasted spend.

Start treating match rate like the vital KPI it is—and watch your acquisition strategy evolve into a profit-driving machine.

I welcome all feedback. Good, bad, everything in between.

Hit reply, and let’s hear it! 👂

📧 Share your thoughts or what you want me to cover next!