Zero Party Data: What It Is and How to Use It

73% of consumers are willing to share personal data in exchange for a personalized experience (Salesforce, 2025). The key is asking for it the right way.

With the death of third-party cookies, tighter GDPR enforcement and growing consumer distrust, companies need a data strategy that doesn't depend on intermediaries. This is where zero party data comes in: information the user gives you voluntarily, consciously and directly.

What Is Zero Party Data

The term was coined by Forrester Research and is defined as:

"Data that a customer intentionally and proactively shares with a brand, including preferences, purchase intentions, personal context and how they want to be recognized by the brand."

The key word is intentionally. We are not talking about data inferred from user behavior (that is first party data), but information the user explicitly declares.

The 4 Types of Data: Full Comparison

To understand the value of zero party data, you need to know the full spectrum:

Type	Source	Consent	Example	Accuracy
Zero party	The user themselves, declared	Explicit and voluntary	"I prefer weekly emails about CRO"	Very high
First party	Behavior on your properties	Implicit (cookie acceptance)	Pages visited, products purchased	High
Second party	First party data from a partner	Contractual	Audience data shared between allied brands	Medium-high
Third party	External data aggregators	Indirect or nonexistent	Demographic segments bought from data brokers	Low-medium

Why Zero Party Data Is Superior

1. Accuracy: the user tells you exactly what they want, no inference needed
2. Consent: natively compliant with GDPR and ePrivacy
3. Trust: builds a transparent relationship with the user
4. Durability: doesn't depend on cookies or browser decisions
5. Actionability: data directly applicable to personalization

Examples of Zero Party Data

To make it clear what type of data we are talking about:

Declared preferences:

• "I'm interested in: CRO, email marketing, web analytics"
• "I prefer content in video format"
• "My monthly marketing budget is 5,000-10,000 EUR"

Purchase intentions:

• "I'm looking for an A/B testing tool"
• "I plan to switch CRMs in the next 3 months"
• "My CRO experience level is intermediate"

Personal context:

• "I'm a marketing manager at a company with 50-200 employees"
• "My industry is fashion ecommerce"
• "My main challenge is improving mobile conversion rates"

Direct feedback:

• "This article was useful" / "It didn't help me"
• "What I like most about your tool is X"
• NPS: "Would you recommend our service? 9/10"

8 Strategies to Collect Zero Party Data

1. Interactive Quizzes and Assessments

Quizzes are the gold standard for zero party data. The user answers questions voluntarily in exchange for a personalized result.

Examples:

• "What is your CRO maturity level?" (assessment with score)
• "Discover which email strategy you need" (quiz with recommendation)
• "Is your site optimized for conversion?" (quick diagnosis)

Typical quiz conversion rates: 30-50%, compared to 3-5% for a standard form.

2. Email Preference Centers

Instead of a simple "subscribe / unsubscribe," offer a preference center where the user can choose:

• Topics of interest
• Sending frequency
• Preferred format (text, video, podcast)
• Professional role and industry

3. Progressive Forms

Don't ask for all information at once. Use progressive profiling:

Interaction	Data Requested
First visit	Email
Resource download 1	Name + company
Resource download 2	Industry + company size
Webinar	Role + budget
Demo	Challenges + purchase timeline

Each interaction adds another piece to the puzzle without overwhelming the user.

4. Post-Purchase and Post-Interaction Surveys

Key moments to ask:

• After a purchase: "What convinced you to buy?"
• After a webinar: "What topic would you like us to cover?"
• After using the product: "What do you mainly use it for?"
• Upon cancellation: "What could we have done better?"

5. Conversational Chatbots

A well-designed chatbot collects zero party data naturally:

• "How can I help you today?" Intent
• "What is your main challenge right now?" Pain point
• "Have you used testing tools before?" Experience
• "When do you plan to make a decision?" Timeline

6. Gamification

Game elements that incentivize data sharing:

• Discount spin wheels ("Spin the wheel: enter your email")
• Digital advent calendars
• Points programs for completing profiles
• Challenges with rewards

7. Interactive Content

• Calculators: "Calculate the ROI of improving your conversion rate"
• Configurators: "Design your ideal optimization plan"
• Comparators: "Which testing tool fits you best?"

Each interaction generates user-declared data.

8. Reviews and Testimonials

When you ask for a review, you get:

• Satisfaction (rating)
• Real use case (text)
• Reviewer profile data (industry, role)
• Implicit permission to use their feedback

Zero Party Data and GDPR: Native Compliance

Zero party data has a natural regulatory advantage: since it is shared voluntarily and consciously, it complies with GDPR principles almost natively. But "almost" is not "completely." You must ensure:

Legal Requirements

1. Clear legal basis: explicit consent or documented legitimate interest
2. Transparent information: the user must know what their data will be used for
3. Specific purpose: don't collect data "just in case"
4. Minimization: only request what is necessary for the stated purpose
5. Right of access, rectification and deletion: implement clear mechanisms
6. Secure storage: encryption and controlled access

Best Practices

• Always explain the "why" alongside the form
• Always offer the option not to answer
• Don't gate essential content behind optional data sharing
• Review and purge data periodically
• Document consent with a timestamp

Use Cases: Zero Party Data in Action

Case 1: Email Marketing Personalization

With preference data (topics, frequency, format), you can create hyper-personalized segments. The result: open rates 29% higher and CTR 41% higher than mass sends (Epsilon, 2025).

Case 2: Web Experience Personalization

If a user declares their industry is "fashion ecommerce," you can:

• Show relevant case studies on the homepage
• Prioritize blog content from their sector
• Adapt the value proposition on landing pages
• Suggest services specific to their vertical

Case 3: More Accurate Lead Scoring

Traditional lead scoring relies on behavior (first party). Adding zero party data such as declared budget, decision timeline and specific pain points multiplies scoring accuracy and improves marketing-sales alignment.

Case 4: Product Development

Responses to surveys and assessments reveal patterns that behavioral data alone can't capture. If 60% of your users say their biggest challenge is "measuring the impact of tests on revenue," you have direct input for feature prioritization.

How to Measure the Impact of Your Zero Party Data Strategy

Metric	What It Measures	Target
Quiz/form completion rate	Engagement with collection mechanisms	>30%
Percentage of complete profiles	Depth of available data	>60%
Segmented open rate vs. unsegmented	Value of personalization	+20% minimum
Conversion of leads with zero party data vs. without	Pipeline impact	+15% minimum
NPS of personalized experience	User satisfaction	>50

Common Mistakes with Zero Party Data

1. Asking too much too soon: creates distrust and abandonment
2. Not using the collected data: if you ask for preferences and then send the same thing to everyone, you destroy trust
3. Not updating the data: preferences change, offer ways to update them
4. Storing without protecting: a data breach involving declared information is devastating for trust
5. Not closing the loop: if the user tells you something, show them you listened

The Future: Zero Party Data as Competitive Advantage

In a cookieless world, the companies with the most direct and transparent relationship with their users will win. Zero party data is not just a legal compliance tactic: it is a business strategy that improves personalization, conversion and retention simultaneously.

Start simple: a preference center in your newsletter or a quiz on your site. Measure, iterate and scale. If you want to see how your website can improve its data capture and conversion, try Scan&Boost or talk to our CRO team.

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Article written by Adrià Vidal, CRO and experimentation specialist at Boost. Want to improve your conversions? Request your free audit.