First-party data is the new targeting: what to collect (and what not to)

Every platform update in the last few years points the same direction: third-party targeting keeps getting narrower, and the brands still growing are the ones who didn’t depend on it in the first place.

First-party data — the information customers give you directly — is the one asset a platform update can’t take away. It’s also the most underused thing sitting in most businesses’ inboxes and order history.

What’s worth actually collecting:

• Email and purchase history, synced to ad platforms as a seed audience for lookalikes — this consistently outperforms interest-based targeting because it’s built from real buyers, not guesses.
• On-site behavior for non-buyers — what someone viewed but didn’t buy is a stronger retargeting signal than almost anything a platform can infer.
• Zero-party data — things customers tell you directly through a quiz, a preference form, or a post-purchase survey. Low volume, extremely high signal.

What I’d avoid collecting: anything you don’t have a clear, compliant reason to use, and anything that requires consent you haven’t actually secured under GDPR. A smaller, clean, consented list outperforms a larger one you’re not confident you can legally use — and it’s the difference between an asset and a liability.

The brands treating their customer list as seriously as their ad account are the ones who’ll still be targeting effectively when the next platform change lands.