New ways to support your measurement with first-party data

April 15, 2021

Developing strong relationships with customers has always been critical for brands to build a successful business. This becomes even more vital in a privacy-first world without identifiers that track users across the web.

To deepen our support for solutions that build on these direct relationships between consumers and the brands and publishers they engage with, we’re updating the global site tag (gtag.js) and Google Tag Manager (gtm.js) to set a new same-site cookie on advertisers’ web domains to help improve how we attribute conversions back to ads.

Consistent with how existing first-party cookies work, the new cookie will be unique and limited to users on your site only. Starting in May 2021, this first-party cookie will enable more accurate attribution of conversions, including instances where a user might engage with more than one of your ads before converting.

Advertisers can opt out of our tagging solutions that use first-party cookies at any time by disabling conversion linking. Learn more.

As always, please ensure you're providing users with clear and comprehensive information about data collection, and obtaining consent where legally required. 

If you have any questions, please don't hesitate to reach out to your account team.

Posted by James Ioannidis, Product Manager, Google Ads

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