Zero-party data vs. first-party data, and why the difference matters

Zero-party data is information a customer volunteers on purpose, like their email frequency preference or their date of birth. First-party data is what you learn by watching what they actually do on your site, app, or in your inbox. The easiest way to differentiate between the two is to think of one as the data purposely given to you, while the other is data you got from observation.

Most marketing teams are drowning in data, but starving for the right kind. You've probably got pixels tracking clicks, cookies logging pages, CRMs full of purchase history, and yet, none of that tells you what a customer actually wants. It just tells you what they did.

Zero-party data and first-party data get lumped together a lot, but they’re not the same thing. They’re collected and used differently, which means mixing them up costs you the thing both are supposed to earn: trust.

Here's the difference between zero-party data and first-party data, why each matters, and how the two work together.

Zero-party data vs. first-party data: comparison chart

	Zero-party data	First-party data
Definition	Shared intentionally and directly by the customer	Collected from a customer's actions and behavior
How it's collected	Surveys, quizzes, preference centers, account settings	Website analytics, purchase history, app usage, CRM records
Example	"I prefer email over text messages"	Opened 4 emails, bought twice in the last 30 days
Customer effort	Requires active participation	Passive, collected automatically
Best used for	Personalizing to stated preference and intent	Personalizing to demonstrated behavior

What is zero-party data?

Zero-party data is anything a customer tells you on purpose. You didn’t have to track anything or depend on your best guessing skills to get the data. The customer intentionally shared it with you when they filled in your form, tapped a button, or answered a question, etc. That’s zero-party data, and it’s useful because it delivers explicit consent and higher accuracy without privacy concerns.

Why it matters

A cookie can tell you someone viewed your web page, but it won’t tell you the viewer’s personal preferences or give you the ‘story behind the click’. Zero-party data can close that gap.

It also sidesteps most privacy concerns entirely, since the customer chose to share the data and knows exactly why they did so. That matters more every year. In fact, 48% of consumers say they feel more comfortable with brands that collect data this way, because there's nothing hidden about it.

How it's used

Teams plug zero-party data straight into personalization and use stated preferences to help shape what a customer sees and when. Some examples of using zero-party data in this way include:

Email cadence: sending weekly instead of daily because that's what the customer actually picked in a preference centre.
Content matching: showing running gear instead of hiking gear because someone said their goal is training for a race.
Birthday and milestone triggers: sending an offer on the real date, not a guessed one.
Onboarding: skipping questions a quiz already answered, instead of asking again a week later.
Sizing and fit: recommending the right size because the customer told you, not because a return history implied it.
Category and lifestyle filtering: automatically suppressing irrelevant products (like hiding non-vegan items) based on explicitly declared dietary restrictions.
Budget tiering: tailoring featured product recommendations to fit the exact price threshold a customer specified in a preference quiz.

Using zero-party data across these types of touchpoints replaces behavioral guesswork with explicit customer direction. Doing this helps to make sure each interaction you have with a customer feels tailored, relevant, and earned.

Benefits of zero-party data

Zero-party data pays off in ways that build on each other. Some of the main benefits revolve around its accuracy and ability to convert browsers into buyers by giving them exactly what they ask for. More specifically, though, the best reasons to use zero-party data include:

Better trust: People are more likely to share information with you when they know how you’ll use it.
Higher accuracy: It comes straight from the source, not an inference.
Fewer returned items: When buyers tell you their exact size, fit, or style, they get the right product the first time.
Stronger loyalty: Customers stay with brands that listen to them and remember what they like.
Cheaper ad costs: You spend less money on ads because you stop guessing what people want and show them the right offers at the right time.
Clearer marketing plans: Knowing your shoppers' actual goals helps you make smarter choices about what products to build and sell.
Privacy peace of mind: It holds up as rules tighten, since you're not relying on tracking that regulators or browsers might restrict next.
Higher-converting: Campaigns built around collecting it, like quizzes or preference surveys, see an average 61% conversion rate.

How to collect zero-party data

Collecting zero-party data is about being intentional with what you want and asking for it. That's really the whole point. Some methods that work great include interactive quizzes ("find your skin type"), preference centres where customers set their own email frequency and topics, short surveys, and polls dropped into a newsletter or checkout flow.

Your main obstacle will be convincing customers to share zero-party data with you. They probably won’t be too thrilled about doing that if there’s nothing in it for them. So, make sure they’re aware of how sharing it will benefit them, whether that’s with a more relevant experience or even some type of reward.

It’s also important to make your questions relevant to help make customers feel more connected and willing to respond. Don’t bombard them with questions that feel intrusive, take too much time, or have nothing to do with what they came to buy.

And remember to be transparent. Give them clear context about why your brand is collecting the information. Doing this will help reduce any hesitation they may have.

A few practical examples of methods to collect zero-party data include:

Website sign-up forms
Post-purchase surveys
Event forms
Product quizzes
Interactive polls
Onboarding forms
Customer preference profiles

…and many more, but these are a good place to start.

What is first-party data?

First-party data is what you collect by watching, not asking. It's built from a customer's actual behavior on your own channels, such as what they clicked, bought, browsed, opened, or abandoned in a cart.

Nobody volunteers this the way they volunteer zero-party data. You gather it because they interact with something you own, whether that's your site, your app, your point of sale, or your email list.

Why first-party data matters

First-party data matters because it shows you exactly how your actual customers interact with your brand, helping you build better relationships without relying on outside trackers.

Marketers who lean on borrowed, third-party tracking are building on rented ground that keeps shifting under them. First-party data is the one asset you actually own. Nobody can deprecate it, restrict it in a platform update, or change the rules on you overnight.

First-party data is also getting more valuable to marketers. This is mainly because alternative options keep getting smaller. Google backed off its plan to kill third-party cookies in Chrome (it scrapped the 2025 deadline back in July 2024 and shifted toward a browser-level opt-in instead), but the direction of travel across the industry hasn't gone away. Safari and Firefox already block third-party cookies by default, and Apple's App Tracking Transparency cut off a huge chunk of mobile ad tracking outright (source: CookieYes, 2026).

How is first-party data used?

First-party data drives modern marketing because it builds every action on what a customer actually did. By paying attention to real behavior, brands can send friendly check-in emails after 60 days of inactivity, show reminder ads for items left in a cart, and notice when someone stops logging in so they can step in before the customer leaves.

That same activity feeds into customer profiles (combining site visits, purchases, and support chats into one clear picture), which then helps brands find new shoppers who act just like their best ones.

Main benefits

First-party data helps you to build better relationships with customers by using facts instead of guesses. Because this information comes straight from your own customers' actions, it offers several key benefits for your business.

Owned outright. Nobody can regulate it out from under you the way third-party cookies get squeezed.
Specific to you. It reflects real behavior with your product, not generic web-wide tracking.
Compounding. The longer someone's a customer, the richer this dataset gets.
Revenue-driving. Brands growing their first-party datasets jumped from 41% to 71% in two years, and orgs that lean into it see a 2.9x revenue lift.
Lower costs. You do not have to pay middleman data brokers to learn about your audience.
Stronger loyalty. Understanding what your current shoppers like helps you keep them happy so they stay with your brand longer.

How to collect first-party data

Collecting first-party data involves creating ‘digital touchpoints’ across channels you own that capture customer activity as it happens. The process starts where your audience interacts with your brand. This could be your company’s website, a mobile app, an email campaign, and so on. Whatever the case, you’ll need to make sure the proper analytics tools, CRM tracking, and account setup flows are in place.

Once that’s sorted, you can begin recording explicit interactions your audience and customers have with your brand (account registrations, newsletter sign-ups, content downloads, etc.). As visitors navigate these platforms, you record the data by unifying these touchpoints into a central database like a Customer Data Platform (CDP). From there, you update each individual's behavioral profile in real time while maintaining clear consent and privacy standards.

It sounds like a lot of work, but the systems and tools you have in place will help do a great deal of the work for you. Some specific examples of ways to collect first-party data include:

Website and app analytics
Purchase and transaction history
Email engagement
Loyalty program activity
CRM and sales records
Product usage data
Point-of-sale data
Social engagement on owned channels
Webinar and event attendance

How first-party and zero-party data work together

On their own, each data type has a blind spot. First-party data shows you what someone did but not why they did it. When you use zero-party data, though, you’ll find out what someone wants but not always what they'll actually do about it.

The good news is that you can make the two work together to get the complete picture. This involves using zero-party data to learn their intentions and first-party data to see if they follow through.

For example, a prospect fills out a form saying they're evaluating new tools because their team is scaling past 50 seats and procurement wants a security review before Q1. That's zero-party data because you’re given their intent, timeline, and blockers, in their own words.

Over the next few weeks, your first-party data shows they've opened the pricing page four times, downloaded the security whitepaper, and had two colleagues register for the same webinar.

Intent plus behavior tells sales exactly when to call and exactly what to lead with. You can then skip the generic pitch and go straight to the security review they already flagged.

That's the pairing at work: intent you can trust, backed by behavior that proves it's real.

Second-party data: the one everyone forgets

Second-party data is someone else's first-party data that’s been shared with you directly. In the real world, this might look like a hotel chain partnering with an airline to swap customer insights. They aren't competitors, but they share the same target audience. Both companies benefit from access to high-quality, trusted data that expands their reach and enriches their customer profiles without relying on shady third-party trackers.

Second-party data is getting more popular in recent years. This is likely due to third-party data sources shrinking, leaving marketers in need to scale but without the privacy exposure of buying from data brokers. Second-party partnerships and data clean rooms (secure environments where two companies can match audiences without either seeing the other's raw customer list) are becoming a standard way to extend reach while keeping full control of who sees what.

Conclusion

Every customer gives you two kinds of proof. Some of it is handed directly to you, such as a stated goal, a clothing size, or a birthday. Some of it, like a page revisit or an abandoned cart, is left behind without a thought. Together, they tell you what someone wants and whether they actually mean it.

The brands making the most of both zero-party data and first-party data are the ones who are asking better questions, listening to the answers, and then checking those answers against what people do next.

Our advice is to start small. Add one preference question to your next form and then pull up your last 10 customers and check whether your emails, offers, and follow-ups actually reflect what they already told you. If they don't, that gap is where next quarter's growth is sitting.