key takeaways
Refusing must be as simple as accepting, and pre-ticking non-essential cookies is not valid consent
A ‘discreet’ banner at the bottom of the page, which does not require any choice, mainly produces unreliable data
Each visitor without an explicit choice is treated as a refusal: your traffic and conversions are underestimated
A well-designed CMP forces a clear choice, which serves both compliance and data quality
Consent Mode recovers some of the lost conversions through modelling, without placing a cookie in case of refusal
What the regulations really impose
Except for trackers strictly necessary for the operation of the site, no cookie can be placed before the explicit consent of the user. This concerns your cookies for audience measurement, advertising and social networks. The rules are detailed by the relevant authority on its dedicated compliance page.
Two requirements are crucial for the future. First, refusal must be as easy as acceptance: highlighting "Accept All" while relegating refusal behind several clicks is a misleading practice, punishable. Secondly, simply continuing to browse no longer counts as consent, nor does a pre-checked box: a clear positive action is required. These two principles have a direct and poorly anticipated consequence: an increasing share of your visitors gives no exploitable signal, and this void has a cost.
The blind spot: what you lose with every refusal
When a user refuses or does not choose, your tools stop seeing them. This missing data then permeates all your decisions. Your analytics tool underestimates your actual traffic and conversions : a disappointing conversion rate is sometimes just a measurement artifact. On the advertising side, the effect is more insidious. The algorithms of Google Ads and Meta optimise based on the conversions they receive; if they lose some, they learn from truncated data and spend your budget less efficiently.
Where to place the banner: the trap of the "discreet" format
For the sake of comfort, many sites choose a small banner at the bottom of the page, which does not interrupt browsing. The intention is commendable, but the effect is counterproductive. As the visitor can continue to browse without making any decision, they never make an explicit choice. However, in the absence of a choice, no consented cookie can be placed: this visitor is therefore treated as a refusal and is excluded from your statistics. In other words, the banner that "does not disturb" is precisely the one that degrades your data the most, since it leaves the majority of internet users in a middle ground that amounts to a no.
Conversely, a visible and hard-to-ignore banner that clearly invites a decision transforms each visitor into a clear signal, one way or the other. Without going as far as a 'cookie wall' that conditions access to the site (a regulated practice), the goal is to provoke a conscious decision, not to circumvent it.
Pre-checked boxes: the right default setting
The tempting reflex is to pre-check everything by large family of cookies, so that 'by default' everything is accepted and data flows. This reflex poses two problems: it is not compliant, as pre-checked boxes do not constitute consent, and it exposes one to a sanction. Conversely, leaving only essential cookies checked is compliant, but when associated with a passive banner, it results in a low consent rate.
The path that reconciles compliance and reliability relies on an explicit and readable choice. The ideal is to offer, at a strictly equal level of simplicity, three clear actions: 'Accept all', 'Reject all', and 'Essential cookies only'. This third button plays a often overlooked role: it provides a clear exit for the hesitant visitor, who would otherwise remain without choice and thus treated as a silent refusal. By giving them a clear intermediate option, you transform a non-decision into an explicit, compliant, and usable decision. A settings panel by family, where non-essential cookies are disabled by default but can be reactivated with one click, completes the system. You do not force the hand, you force the choice. And data that reflects real decisions, even partial ones, is infinitely more usable than artificially inflated and legally fragile data.
CMP and Consent Mode: reconciling compliance and reliability
This is the role of a CMP (Consent Management Platform): to display the banner, block trackers before consent, collect and prove consent. When properly configured, it impacts both your compliance and your legitimate consent rate, through a clear and reassuring message.
Even so, a portion of visitors will always refuse. To legally fill this gap, Google offers Consent Mode: in the event of a refusal, no cookie is placed, but an anonymous and aggregated signal is transmitted, from which conversion modelling estimates unobserved sales.
Configuration | Compliance | Data quality | Advertising performance |
No management or non-compliant banner | Risk of sanction | Distorted and unreliable data | Degraded optimisation |
Compliant but basic CMP | Assured | Unfilled data gaps | Partial |
Active CMP (accept / refuse / essentials) + Consent Mode | Assured | Partially filled gaps | Enhanced |
Making consent an asset, not a constraint
Treating the banner as a simple checkbox, placed once and forgotten, creates your own blind spots. When thought through correctly, consent becomes a lever for management: the clearer the collection, the more complete the data, and the more accurate your budgetary decisions.
One last point: no configuration will give you perfect data. Modelling remains an estimate, to be read as a trend and not as an exact figure. Performance does not come from a clever adjustment of the banner, but from overall consistency: an honest collection, an up-to-date CMP, and a clear reading of the indicators. It is this rigor, over time, that distinguishes sites that know where their budget is going from those that proceed blindly.
FAQ
Is a banner at the bottom of the page, which does not interfere with navigation, a good idea?
For comfort, yes; for your data, no. As it does not impose any choice, most visitors remain without consent and drop out of your statistics.
Can I pre-check the cookies to collect more data?
No. Pre-checked boxes do not constitute valid consent and expose you to a penalty. Consent must result from a positive action.
How can I ensure my data is reliable while remaining compliant?
By forcing a clear choice: 'Accept All' and 'Reject All' as simple as each other, with granular settings disabled by default but easy to activate.
Is Consent Mode compliant?
Yes in principle: it does not place any cookies in the event of a refusal and only transmits anonymous and aggregated signals used to estimate missing conversions.