The consent platform is the component that tells your tags what they are allowed to do. Choose one that integrates cleanly with Google Tag Manager and Consent Mode v2, or you spend weeks debugging tags that fire too early, never fire, or fire for the wrong region. This guide sets the requirements, compares the common platforms, and ends with the configuration checklist that applies to all of them.
What the Platform Must Do
- Show a compliant banner with equal Accept and Reject options where required, and granular choices.
- Set Consent Mode v2 defaults before any Google tag fires, ideally per region.
- Send the consent update to Google tags when the visitor chooses, and remember the choice.
- Expose the choice to GTM, either through a built-in GTM template or a reliable dataLayer event, so non-Google tags can be held and released.
- Scan and classify cookies and keep the declaration current.
- Geo-target behaviour: opt-in regions, opt-out regions, no banner elsewhere.
- Provide a consent log for compliance.
- Optionally, pass consent state to server-side GTM.
The Common Options Compared
| Platform | GTM integration | Consent Mode v2 | Geo-targeting | Free tier | Notes |
|---|---|---|---|---|---|
| Cookiebot by Usercentrics | Official template | Native | Yes | Small sites | Widely used, strong scanner, paid above small page counts |
| CookieYes | Official template | Native | Yes | Yes | Good value, easy setup, popular on WordPress and Shopify |
| Usercentrics | Official template | Native | Yes | Trial | Enterprise features, TCF, server-side support |
| Complianz | WordPress plugin with GTM support | Native | Yes | Yes | WordPress-focused, strong documentation |
| OneTrust | Template and SDK | Native | Yes | No | Enterprise, complex, best for large organisations |
| Iubenda | Template | Native | Yes | Limited | Combines policies and banner |
| Termly | Template | Native | Yes | Limited | Simple, policy generation included |
| Platform-native banners such as Shopify's | Built in | Partial, improving | Limited | Yes | Convenient, but check Consent Mode v2 support and GTM signalling before relying on them |
Any of the first four handles a typical small or mid-size business well. The choice usually comes down to platform fit, Complianz or CookieYes for WordPress, Cookiebot or CookieYes for Shopify and custom sites, Usercentrics or OneTrust for enterprises with legal requirements around TCF and consent logs.
Decision Factors
- Your platforms. WordPress favours Complianz; Shopify has a native banner plus app options; custom and headless sites want a template-based platform.
- Regions. If you serve both the EU and the US, you need geo rules for opt-in versus opt-out.
- Vendors. If you only run Google, Meta and TikTok through GTM, you do not need TCF. If you run programmatic display, you do.
- Server-side. If you run server-side GTM, choose a platform that can pass consent to the server or rely on GTM forwarding Consent Mode signals, which the GA4 client does.
- Cost at scale. Scanner page limits and monthly sessions drive pricing; estimate for a year ahead.
- Google certification. Required for EU and UK ads personalisation.
Configuration Checklist, Any Platform
- Install the platform's GTM template, not its raw script, unless the template is unavailable.
- Fire the template tag on the Consent Initialization trigger.
- Set regional defaults: denied for opt-in regions, granted or denied elsewhere according to your policy, and confirm
ad_user_dataandad_personalizationare included. - Set Google tags to No additional consent required for Advanced mode, or require the relevant signal for Basic mode.
- Require
ad_storageon Meta, TikTok, LinkedIn, Microsoft and other ad tags; requireanalytics_storageon heatmaps and non-Google analytics. - Add the platform's consent update dataLayer event as a secondary trigger for tags that should fire immediately after acceptance.
- Turn off the platform's automatic script blocking if it conflicts with GTM's consent handling; keep one mechanism.
- Match the cookie declaration to reality by running a scan after tags are final.
- Test as a new visitor in each region, using a VPN, for Accept, Reject and Customise paths. The Consent Mode v2 guide on this site has the test steps.
- Verify Consent Mode status in Google Ads Diagnostics and GA4 Admin after a day.
Common Mistakes
- Banner that shows but never updates Consent Mode because the raw script was used without the signal calls.
- Platform blocking plus GTM blocking, with tags released by one and held by the other.
- Defaults set globally to granted so the banner is decorative.
- Shopify's native banner assumed to handle GTM tags, when GTM needs explicit consent settings.
- Testing with a cached consent choice so the banner never appears.
Outcome
A banner that is compliant where it needs to be and invisible where it does not, Google tags that model what they cannot observe, non-Google tags that wait for permission, and a consent log for the day someone asks. Pick the platform that fits your site, then spend the time on the configuration, which matters more than the brand.