How to build a zero-party data strategy that actually replaces third-party cookies

Why zero-party data matters now

I've been watching the slow death of the third-party cookie for years, and the urgency to build alternatives has finally hit home. Cookies weren't just a convenience—they powered targeting, measurement, and personalization at scale. But relying on a technology controlled by browsers and external vendors was always fragile. Zero-party data gives us something sturdier: information that customers willingly share, intentionally, and often with context. That makes it more accurate, more trustworthy, and more resilient to privacy shifts.

Zero-party data isn't a silver bullet. It won't automatically recreate every capability of a third-party cookie. What it does do, when handled well, is create a direct relationship between brands and people—one that can actually deepen loyalty and reduce dependency on opaque intermediaries.

What exactly is zero-party data?

In plain terms: zero-party data is information a customer intentionally and proactively shares with you. That can include preferences, profile data, purchase intentions, feedback, and how they'd like to be contacted. Think preference centers, quizzes, surveys, and direct messages. Unlike first-party behavioral data (what someone does on your site), zero-party data is explicit—it's consent plus context.

Core principles I use when building a zero-party data strategy

Transparency: I always tell people why I'm asking for information, how it will be used, and what value they'll get in return.

Reciprocity: People give information when they receive something meaningful in exchange—relevance, convenience, discounts, or better experiences.

Context: I capture data where the visit makes sense—product pages for product preferences, checkout for delivery preferences, onboarding for intent.

Control: I design experiences where customers can update preferences easily and see what's stored about them.

Data hygiene: Periodic validation and simple opt-outs keep the database accurate and GDPR-friendly.

Practical ways I collect zero-party data

Here are tactics I've implemented that actually work:

Preference centers: Beyond "email frequency," build centers that let users pick product categories, communication channels (SMS, email, app), and content topics. Make this a clear step during sign-up and accessible in account settings.

Onsite micro-surveys: One-question surveys at strategic moments—after purchase ("How did you hear about us?"), after browsing ("Which of these looks best?"), or post-support interactions—generate high response rates.

Quizzes and configurators: Interactive experiences (e.g., "Find your perfect moisturizer") double as engaging tools and rich preference collectors. Brands like Glossier and Birchbox do this well.

Progressive profiling: Instead of asking everything at once, request small bits of info over time, tied to a benefit—faster checkout, tailored recommendations, or loyalty points.

Loyalty programs: Use tiered incentives: provide more personalization for members who share more data. Starbucks and Sephora illustrate how loyalty + personalization equals higher lifetime value.

Checkout touchpoints: Ask for delivery, gifting preferences, and product use intentions during purchase—people expect to provide practical details there.

Post-purchase feedback flows: Ask about satisfaction and intended use. Those responses are gold for segmentation and product development.

Designing the experience: what to test first

Start by mapping your customer journey and identifying where asking for data feels natural. I always prioritize these tests:

Account creation: ask one high-value preference (product category, usage frequency).

First purchase: request purpose-of-use and any sizing or special requirements.

Email welcome series: include a short preference check to refine content from the start.

Abandoned cart: ask why they paused—price, shipping, product uncertainty?

Conduct A/B tests on incentive types (discount vs. exclusive content), question wording, and timing. Often the difference between a 5% and a 35% response rate is simply changing “Tell us your favorite styles” to “Which of these three styles do you love most?”

Technology stack and data flow I recommend

To make zero-party data actionable, you need an integrated stack. Here's a simple table I use to plan components.

Function	Example tools
Data capture	Onsite widgets: Typeform, Qualtrics, Intercom; native CMS forms
Customer data platform (CDP)	Segment, mParticle, Tealium
CRM & personalization	Salesforce, Klaviyo, Braze, Dynamic Yield
Analytics & measurement	Google Analytics 4, Adobe Analytics, Mixpanel
Consent & privacy	OneTrust, Cookiebot, in-house consent layer

The key is that zero-party inputs feed the CDP and CRM directly, and those systems power segmentation and personalized journeys across email, onsite, and ads (when permitted). I maintain a canonical schema for preference types so that "size: M" or "style: minimalist" are standardized across tools.

Segmentation and activation strategies that work

Once you have zero-party attributes, replace broad targeting with narrow, intent-led segments. Examples I've used:

Purchase intent segments: People who say they're "planning to buy in 30 days" get a special nurturing series with product comparisons, reviews, and an exclusive discount at 21 days.

Content preference segments: If someone expresses interest in "sustainable packaging," serve content and product collections tied to that topic.

Channel preference: Respecting channel choice increases engagement—if a user chooses SMS, send timely restock alerts there instead of email.

Product-fit segments: For complex products, use quiz outcomes to send personalized onboarding that reduces returns and increases satisfaction.

Measurement: how I prove zero-party works

Measurement shifts from cookie-based attribution to cohort and lift analysis. I focus on:

Response rate and enrichment—how many profiles have meaningful zero-party fields filled?

Engagement lift—do users with preference data open more emails, click more, or spend more?

Conversion lift—A/B tests where one cohort receives personalization based on zero-party data and a control gets generic messaging.

Retention and CLV—are people with shared preferences sticking around longer?

For example, in one campaign I ran, personalized email content based on quiz responses increased click-through by 42% and revenue per email by 28% versus the control.

Privacy, consent and trust: non-negotiables

Zero-party data is only valuable if people trust you. I never hide what I'm collecting or why. Practical steps I always implement:

Clear, plain-language explanations at the point of collection.

Granular consent options and easy ways to change preferences.

Data minimization—only ask for what you need, and archive or delete stale attributes.

Secure storage and access controls; treat zero-party data as sensitive.

Regular audits to ensure promises match practice (e.g., if you promised "no third-party sharing," verify that's enforced).

Common pitfalls and how I avoid them

Asking for too much too soon: progressive profiling solves this.

Poor UX: ensure forms are short, mobile-optimized, and visually clear.

Not operationalizing data: capture without activation is wasted effort—build immediate use cases.

Siloed data: send zero-party attributes into a CDP and keep them synced across channels.

Treating zero-party as static: preferences change—build routines for re-confirmation and updating.

Where zero-party won't replace cookies

I want to be honest: zero-party data doesn't eliminate the need for other signals. Behavioral data, contextual targeting, and aggregated privacy-safe measurement (like cohort-based approaches or server-side attribution) will still be necessary for scale. But when combined, these methods reduce dependency on third-party cookies and give you a cleaner, consent-first approach to personalization.

Adopting zero-party data is as much about mindset as technology. When teams stop thinking of data as something to harvest and start thinking of it as a relationship currency—earned, respected, and reciprocated—you build strategies that survive regulatory change and build customer loyalty. Start small, prove value quickly, and scale what works. You'll end up with a richer, more durable marketing foundation than any cookie ever provided.