Signal Hub

Ads Performing Worse After a Consent Update: What Actually Changed

Diagnostics and decisions · 4 min read · by Anna Viggeborn

When a new consent banner goes live, the number of events your platforms receive changes on the same day. Sales may be untouched. Reporting is not.

What a consent change actually does

  • Events are blocked entirely for users who decline.
  • Events are sent with fewer customer parameters, which weakens matching.
  • Tags load later, so short sessions are lost.
  • A banner covering the confirmation page prevents the purchase event from firing.
  • Consent mode sends modelled rather than observed data for part of your traffic.

How to confirm it is the cause

1. Find the exact release date
2. Compare orders in your own system before and after
3. Compare event volume per platform before and after
4. Check the consent acceptance rate
5. Test the confirmation page with consent declined

How to recover signal legitimately

  • Improve banner design and wording to raise genuine acceptance.
  • Make sure the banner never blocks the confirmation page.
  • Use server side events for consented users so matching stays strong.
  • Implement consent mode correctly so modelling can work at all.
  • Rebaseline your targets against the new measured level.

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