First-Party Data: Why It’s Becoming the Backbone of Digital Marketing in Belgium | Articles

Over the past few years, the digital landscape has changed quickly. Third-party cookies are disappearing, platforms are reshaping how data flows, and regulators are raising the bar on transparency and consent. At the same time, advertisers still need accurate measurement, relevant targeting, and ways to grow efficiently.

The result? First-party data has moved from “nice to have” to “essential”. It is now the most durable solution for marketing strategies.

The companies that succeed in a cookieless world are the ones that build strong first-party data foundations. The ones who don’t, are already seeing cracks: shrinking remarketing pools, less reliable attribution, and more difficulty in scaling.

So what is happening, why does first-party data matter so much, and what does it take to get it right?

What do we mean by first-party data, and why is it so valuable?

First-party data is all the information your business collects directly from your customers and prospects such as website behaviour, logged-in sessions, email engagement, CRM records, purchases, loyalty programmes or in-store data.
Because it comes straight from real interactions with your brand, it’s high quality, privacy-safe and future-proof. It’s also the only type of data that remains fully usable as third-party identifiers disappear. In a world where platforms restrict visibility and cookies break, first-party data gives you continuity. Integrating CRM data becomes the most reliable alternative for powering remarketing, audience targeting and measurement.

It also powers what marketers care about most:

  • Smarter targeting because you actually understand who your audience is

  • Better personalization

  • More accurate measurement thanks to deterministic, consented signals

  • Stronger customer relationships built on value, not intrusive tracking

  • Better signals for the algorithm to better optimise the campaigns thanks to machine learning.

Moreover, with 1st Party Data activation, advertisers can:

  • Re-engage past users with higher intent

  • Exclude existing customers to reduce wasted spend

  • Build lookalike audiences that closely resemble top converters

  • Improve delivery algorithms on platforms like Meta and Google

  • Segment your audience for more relevant messaging

The impact is significant as it gives better CPAs, stronger ROAS, fewer wasted impressions and more conversions from the same budget.

The other side of the coin: challenges marketers must be aware of

Of course, first-party data doesn’t magically solve everything. It comes with its own challenges, and we see three recurring ones.

  • The first is scale: Your first-party audience is limited to the people who already interact with you. However, people do not always accept the cookies, which makes it harder for advertisers to reach them back. Indeed, companies often struggle with small 1st party audience size and have to combine their first-party data with other signals (contextual, lookalike,...) to broaden their audience. For upper-funnel reach, you still need contextual signals, retail media, publisher partnerships or lookalike modelling.

  • The second challenge is complexity: Bringing data together from your CRM, website, app, call centre or offline systems requires coordination and often dedicated technology.

  • The third is governance: GDPR still applies, collecting data doesn’t mean you can use it however you want. Consent must be clear, storage must be controlled, and you need internal rules to keep everything clean and compliant.

None of these are blockers, but they’re real. And ignoring them leads to messy data, weak personalization and headaches later.

A strong 1PD setup starts with understanding the data

Before activating any 1st Party Data solution, advertisers must clarify their internal data landscape:

  • What information is available (email, hashed phone, purchase history, product preferences…)?

  • What is the volume (active users, past users, churned customers…)?

  • How clean and structured are the datasets? It’s important to have clear and structured datasets with the most important information required for the business, to avoid irrelevant or overly detailed information.

  • Are consent and GDPR requirements properly documented?

  • Can the data be used for external activation (Meta, Google, publishers) or shared through privacy-safe environments?

A clear diagnostic determines whether the activation path will be lightweight or require deeper transformation.

There are different levels of 1st Party Data activation

Not all solutions deliver the same impact. Generally, three maturity levels exist:

Level 1: Basic CRM uploads (Low effort)

Here, you just need to manually upload CRM lists into Meta or Google. It’s fast to implement and can already improve remarketing quality and targeting. However, with this solution, advertisers tend to forget refreshing or don’t refresh their data enough. This implies that they are working with outdated or low-quality data.

  • Pros: Easily implemented

  • Cons: Not enough refreshed which leads to outdated or low-quality data

Level 2: Automatic CRM integrations (Medium effort)

Here, you need to connect CRM systems via tools like Zapier, HubSpot, Shopify, or via API. It allows the advertiser to keep its audiences fresh, to improve the algorithm learning and reduce manual work.

  • Pros: Reduce manual work to keep the audiences up to date

  • Cons: The implementation is heavier

Level 3: Full advanced setup (Medium–High effort)

This includes:

  • Conversion API integrations

  • CDP connections (Segment, Hightouch, Census, Treasure Data…)

  • Data Clean Rooms used with partners (InfoSum, LiveRamp,...)

This level brings the highest uplift and prepares the advertiser for a fully cookieless reality. However, this solution takes much more time to integrate.

  • Pros: It brings the highest uplift and prepares advertisers for a cookieless world

  • Cons: The implementation takes time and can be costly depending on what the advertisers already have.

Why do we strongly recommend acting now?

Cookie loss is permanent. Platform restrictions are here to stay. Measurement won’t suddenly go back to the “good old days”. But brands that invest in first-party data don’t just adapt, they gain an edge

  • They keep attribution alive through server-side signals.

  • They build audiences that no browser update can erase.

  • They personalize in a way that customers appreciate.

  • They spend smarter because they understand the full customer journey.

  • They stay compliant without sacrificing performance.

  • They have access to better signals to feed the algorithm and optimize the campaigns.

The cookieless future is not a threat. It’s a shift. And first-party data is the most reliable way to embrace it.


publication auteur Marie Capart
AUTHOR
Marie Capart

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