Retail media is on fire. Every retailer is building a network. Every brand is testing campaigns.

But in a sea of impressions, clicks, and ROAS reports, one question cuts through the noise: are you actually winning new customers?

What “New to Brand” Really Means

A New to Brand (NTB) customer is someone who buys your brand for the first time within a set period.

Think of it this way: If a shopper buys Dove shampoo today, and they haven’t purchased Dove in the last 12 months, they’re New to Brand.

It’s not a repeat. It’s not a switch between SKUs. It’s true acquisition.

And that matters, because growth in any category comes from penetration: getting more households to buy your brand, not just selling more to the same ones.

How the Industry Measures It

Most retail media platforms calculate New to Brand using a lookback window on transaction data.

• Amazon Ads tags a buyer as NTB if they haven’t purchased the brand in the past 12 months.
• Walmart Connect applies the same logic, identifying NTB households at the brand level.
• Tesco Media & Insight includes NTB rates and cost per NTB in its campaign dashboards.

The formulas are straightforward:

• NTB % = NTB buyers ÷ all campaign buyers
• NTB revenue = sales generated from NTB buyers
• Cost per NTB = media spend ÷ NTB buyers

This makes NTB one of the few metrics in retail media that goes beyond exposure to show customer acquisition.

The Limitations

As powerful as it sounds, the standard NTB calculation has blind spots.

• Fixed windows: A 12–24 month lookback doesn’t fit every category. Beer and detergent don’t share the same buying cycle.
• Brand-only tagging: If a shopper moves from one SKU to another in the same brand family, they often get counted as “existing,” even if it’s a new product launch.
• Partial data: Loyalty programs alone miss many transactions, underestimating NTB rates.

The result? Campaigns can look less effective than they truly are; or worse, insights steer budgets in the wrong direction.

How Footprints AI Reframes New To Brand Customers

At Footprints AI, we’ve taken the idea of New to Brand further, making it sharper, more accurate, and more actionable.

1. SKU-level precision We measure NTB at the level of each product, not just the umbrella brand. Essential for launches and line extensions.
2. Omnichannel attribution Our Homomorphism engine connects in-store and online behavior, linking NTB to ads on screens, apps, web, and off-site channels.
3. Adaptive lookback windows We tune measurement to category cycles. Beer might use 3 months. Detergent, 12–18 months. Each follows its natural rhythm.
4. Incrementality proven NTB isn’t just counted, it’s benchmarked against a control group. That way, we don’t just report outcomes, we prove causality.

The result: NTB becomes not just a label, but a growth signal you can trust.

Why This Matters

For brands, NTB is proof of penetration growth, the single biggest driver of brand growth, as shown in Byron Sharp’s How Brands Grow. It’s not just about selling more to existing buyers. It’s about expanding the base of households who choose your brand.

For retailers, NTB elevates your media network. You’re not just offering impressions; you’re providing a measurable engine of market share growth. That makes your inventory more valuable, and your role as a growth partner irreplaceable.

In a landscape crowded with metrics, NTB is the one that proves real impact.

The future of retail media won’t be judged by outputs. It will be judged by outcomes.

And New to Brand is the outcome that matters most because it proves growth, not just activity.

So the real question is this: When was the last time you looked at your NTB rate for your retail media investment and what does it say about your campaigns?