Question : Open tracking and the CNIL recommendation: what Mailpro does, what you must do

Since the CNIL's recommendation of 14 April 2026, measuring the opens of your emails for marketing purposes (the "tracking pixel") requires that your recipients be informed and able to opt out. This applies whenever you send to recipients in France. Mailpro™ automatically deploys the notice, the opt-out and adapted statistics across all your campaigns: there is nothing for you to configure. You do, however, remain the data controller for how you collect your addresses.

The essentials in 30 seconds. A tracking pixel (an invisible image) powers your open rates. The CNIL asks for an easy notice + opt-out. You are the data controller; Mailpro is your processor and supplies the tooling. Nothing to configure on your side, and your statistics stay reliable (opt-outs are shown separately and excluded from the calculation).

What does the CNIL recommendation change?

Published on 14 April 2026, it clarifies that using a pixel to measure campaign performance falls under the recipient's prior consent. This consent is separate from the agreement to receive your emails: an address that opted in to your newsletter does not, on its own, amount to consent for open tracking.

Who is responsible for what?

You decide to send, collect your addresses and set your purposes: you are the data controller and must keep proof of consent. Mailpro supplies the technical solution and acts as your processor, on your instructions. No tool can make you compliant in your place.

What does Mailpro put in place, concretely?

Four mechanisms, applied automatically to your campaigns: a "preference centre" link in the footer of every email; a page where the recipient declines or re-enables tracking in one click, without re-typing their address; immediate enforcement of the opt-out; and adapted statistics. Automated and API sends will follow.

A recipient who opts out of tracking still receives your emails: refusing the pixel is not unsubscribing. The two choices are offered separately.

Is the opt-out really effective?

Yes. Your next sends no longer contain a pixel for that person, and emails already sent — if they are reopened later — are no longer counted either. This is the effectiveness requirement set by the CNIL, applied within minutes.

Do my statistics stay reliable?

Yes. Recipients who have opted out appear in a "Not measured" tile and are excluded from the denominator of your open rates: a 40% rate is still a true 40% of measurable recipients. Your click, unsubscribe and deliverability rates are unaffected.

Does the opt-out apply to every Mailpro sender?

No. The choice is recorded per sender: a recipient who opts out of tracking on your emails does not automatically opt out with another sender, and vice versa.

What do I need to do on my side?

For your existing lists, nothing immediate: the notice and opt-out we deploy cover the transitional period. For your future sign-ups, add a note about open tracking to your forms (the CNIL offers model wording), keep proof of your consents, and describe the use of pixels in your privacy policy.

I build my own footer: what should I do?

Nothing new. Keep placing your usual unsubscribe marker ($UnsubscriptionLink$): Mailpro replaces it at send time with the recipient's personal link, which leads to the preference centre (unsubscribe, data and tracking choice in one place). Without the marker, the sentence with the link is added automatically.

What about my transactional emails?

The CNIL exempts certain strictly limited uses from consent: security and authentication, and individual deliverability measurement (identifying inactive contacts) on emails requested by the recipient — typically transactional emails. These exemptions come with strict data-minimisation conditions.

Where can I find the official text?

The CNIL recommendation on tracking pixels (PDF) and the announcement of 14 April 2026. On related questions of where your data sits and how it is governed, see is my email marketing data subject to US law and do I need Standard Contractual Clauses.

Need help? Our support team is available for anything about the tool. For your specific situation (qualifying your processing, drafting your forms), speak with your lawyer or DPO.

This page is general information and does not constitute legal advice.