The power of zero- and first-party data: A marketer’s guide to smarter engagement

Many marketers are still treating data like an all-you-can-eat buffet.

“More stations! More varieties! More options!” They pile their plates high with website visits, bounce rates, ad impressions, email opens, click-through percentages, social media engagements, and third-party data, hoping quantity would somehow transform into quality insights.

But the dining experience is changing.

With 84% believing data privacy is a human right and close to half (45%) of consumers distrusting companies with their website behavior and cookie data, the buffet is shrinking. Third-party cookies, once a main dish, are becoming harder to find on the menu, and privacy regulations now stand like nutrition labels on every dish, forcing marketers to rethink their data diet, and whether any of it still nourishes real insight.

This shift, while alarming at first glance, brings remarkable opportunities.

Zero- and first-party data, willingly shared by customers, generates 2.9x the revenue per ad compared to third-party alternatives. When someone directly tells you what they care about or shows you through their actions, they’re essentially inviting you to their table.

This kind of data offers permission to market and the intelligence to do it well. It allows you to honor privacy, strengthen customer relationships, and dramatically improve performance all at once. More importantly, it sets the stage for a lasting competitive edge.

Because transparency builds trust.
Trust encourages sharing.
And sharing enables the kind of personalization that makes customers stay long after the cookies are gone.

1. Why is third-party data losing its value?

Third-party data has been marketing’s go-to solution for years. It allowed marketers to track users across websites, display retargeting ads for abandoned products, attribute conversions, and build detailed audience segments based on browsing behaviors.

However, this model is now fracturing across browsers technically, legally, and ethically. Google Chrome, which accounts for around 65% of browser traffic, initially announced plans to phase out 3P cookies in response to growing privacy concerns and regulatory pressure from laws like GDPR and CCPA. After multiple delays, Google’s 2024 update confirmed it would preserve user cookie choice rather than enforce a full deprecation. Meanwhile, Safari and Firefox already block 3P cookies by default, creating an unreliable tracking environment for marketers.

Beyond technical fragmentation, third-party data comes with serious flaws:

• It often misidentifies users, can’t distinguish between multiple people using the same device, and degrades rapidly as cookies are cleared.
• Even when available, it’s hard to act on. It typically uses incompatible identity structures, lacks contextual relevance, and typically arrives disconnected from your first-party systems.
• Integrating it into your stack is time-consuming, technically complex, and by the time you do, it’s often already outdated.

The most significant problem, however, is trust. Customers today expect transparency. Brands that openly gather information, give customers control over their data, and offer fair value in return are able to earn ongoing trust and better access to data. Those that operate in the shadows risk losing both data access and customer goodwill.

2. Discovering gold in your own backyard

While marketers have been prospecting far and wide with third-party data, many have overlooked the rich resources accumulating right under their noses:

• Zero-party data, as in the information customers happily hand over: preferences, survey responses, product ratings, and personal details they’ve consciously shared. This is the gold standard because it comes with built-in customer consent.
• First-party data, which is what customers show you through their behavior. It captures their digital footprint across website interactions, purchase history, and how they engage with your content. This data exists within your own systems and provides rich and reliable behavioral insights.

Forrester merely confirms what the wisest marketers already suspected: 56% of companies would happily trade their third-party data for something better. Ironically, these better options have been within reach in your own database backyard all along.

Now, let’s say you’ve actually done everything right. You’ve collected zero-party preferences from customers and have gathered rich first-party behavioral data from your owned channels.

Congratulations! You now have premium ingredients sitting in separate pantries across your organization.

The harsh truth is that even the best customer data provides limited value when it’s trapped in disconnected systems. Your email platform knows open rates but can’t see website behavior. Your CRM tracks conversations but doesn’t know support history. Your analytics tool measures page views but misses offline interactions.

According to BCG, less than one-third of marketing teams successfully integrate data across channels. This visibility gap creates real business problems that frustrate both marketers and customers. A customer explicitly tells you they’re interested in Product A through a survey (zero-party data), but your sales team calls them about Product B based on a misaligned segmentation rule. Or worse, your company sends a “How’s your new purchase working out?” email on the same day the customer filed a support ticket about the product not working.

These disconnects happen because a lot of companies still follow an outdated model:

Collect → Store → Analyze → Maybe Act.

This approach treats data as something to accumulate rather than activate, resulting in insights that arrive too late to impact customer experiences.

Our suggested model is cyclical, dynamic, and self-reinforcing:

Connect → Contextualize → Segment → Personalize → Iterate → Repeat.

Each cycle feeds the next. As new customer signals come in, they immediately influence how you group people, what you offer them, and when. The loop is constantly improving, and over time, your messages become more relevant, your results clearer, and your relationship with customers stronger.

3. What do marketing teams achieve with a single customer view?

Customer Data Platforms (CDPs) are perfect for bringing this model to life. They connect your marketing, sales, and support systems to maintain a single, real-time view of each customer, no matter where the data comes from. What a customer clicks, shares, or says to support no longer lives in separate systems; it all informs the next message, the next experience, the next offer. Precision targeting becomes second nature because your segments aren’t built on assumptions. Instead, they’re shaped by real behavior, timing, and genuine customer intent.

This clarity doesn’t only improve marketing. It aligns teams. Product sees what features customers care about. Support understands the context behind every ticket. Sales knows who’s truly ready to buy. With a single customer view powering every touchpoint, you stop working in fragments and start acting like one organization.

Even compliance shifts from a limitation to a strength. CDPs are built for consent, so personalization never strays beyond what’s appropriate. And as all of this starts to flow, your marketing stops being a disruption and starts feeling like part of the relationship—relevant, timely, and welcome. You waste less on the wrong audiences and focus more on the people who are ready to engage. And because it’s built on data you actually own, it’s a strategy that holds up no matter how the technology landscape shifts next.

4. CDP magic across your marketing department

“So I’ve connected all this customer data… now what?” Fair question! Let’s give you a quick tour of how your newly connected zero and first-party data, powered by a CDP, transforms every marketing function you’re running today.

• Email marketing becomes about timing and relevance instead of volume. You’ll send fewer messages that get better results because they arrive when customers actually need them.
• Content marketing gets simpler and more effective. You’ll stop guessing what topics might work and start creating what you know your customers want.
• Social media marketing focuses on real connections rather than generic engagement. You’ll create posts for specific customer segments that genuinely resonate.
• Product marketing speaks directly to customer problems. You’ll naturally describe how you solve specific challenges instead of just listing features.
• Performance marketing spends money more effectively. You’ll stop wasting budget on audiences that look promising but never convert, and invest more in segments with proven interest.
• Event marketing shifts from generic programming to tailored experiences. You’ll design content and networking opportunities that match what attendees actually care about.

The truly remarkable thing about this approach goes beyond the immediate ROI boost. The shift to zero- and first-party data aligns good business with good ethics. Customer trust, data quality, and personalization all reinforce each other in a virtuous cycle. Your competition would still be debating cookieless strategies while you’re busy building something infinitely more valuable: a business that customers actively want to share data with. That isn’t merely good marketing. That’s checkmate.

Fragmented customer profiles mean surface-level personalization and wasted ad spend. Our AI solutions built specifically for marketing teams unifies 0P and 1P data into coherent journeys that make marketing feel like a natural extension of the customer relationship. Explore how this approach is reshaping performance metrics for forward-thinking brands.