Troubleshoot your sitewide tagging
For the most accurate measurement of your Google Ads campaigns, make sure that you're using a sitewide tag, which is able to set cookies in the same domain as your site (known as first-party cookies). If you have auto-tagging enabled, those first-party cookies are able to store the GCLID parameter following a click. Then, when the same tags fire on the conversion page, it uses the stored GCLID to properly measure conversions.
If you've already implemented one of our sitewide tag solutions (i.e. global site tag (gTag), Google Tag Manager or Google Analytics) and some issues are still being flagged about your account, follow the steps below to guarantee your conversions are being measured accurately.
Check if you have enabled auto-tagging
In order to accurately measure conversions, you need to enable auto-tagging in your Google Ads account. This allows Google to automatically add the GCLID parameter to your landing page following an ad click, which is then stored in a first-party cookie deployed by one of our sitewide tagging solutions. (See Instructions here.) You can also check if auto-tagging is actually working by following these instructions.
Auto-tagging is compatible with ValueTrack parameters. If you need to add additional parameters to your URL, refer to this article.
Check for previous tags on your conversion pages
Make sure that you have removed any legacy tags (i.e. old Google Ads conversion tracking or old Floodlight tags) from your conversion pages to avoid double counting. To check that, you can use Google Tag Assistant and, in your Google Ads account, go to Tools > Conversions > Select a conversion > Webpages. Go to the web page link and check if there are old tags in place. If so, remove them and only keep the sitewide tag*.
*Only applicable if you're using the global site tag (gTag) or Google Tag Manager. If you're using the option which links Google Analytics to Google Ads, you can keep your legacy tag.
If using Google Tag Manager, don't forget to enable Conversion Linker
The Conversion Linker tag is used to store click data in first-party cookies associated with your domain. This functionality helps ensure that conversions are measured effectively. Deploy a Conversion Linker tag on any page where visitors may land after they click an ad or promotion. In fact, we recommend that you have the Conversion Linker tag fire on all pages.
Check for multiple domains or multiple Google Ads accounts
If you have more than one domain in your Google Ads account, make sure that you have a sitewide tag solution in all of them. If you're using the solution which links Google Ads to Google Analytics, make sure that you've linked all Google Analytics accounts/views to your Google Ads account.
If you have more than one Google Ads account, make sure that all conversions in each account are covered by a sitewide tag solution. It could be that Google Analytics is not linked to all accounts, or that you have multiple domains and some contain sitewide tags while others don't.
Check the domain of conversion pages
The conversion page needs to be the same domain as the landing page of the ad, or you'll need to implement cross-domain tracking. (See the instructions for gTag for Google Ads conversion tracking, Google Analytics and for Google Tag Manager.) Try to see if there is a pattern, e.g. a different domain, path or subdomain. We can distinguish three cases:
- Same domain as landing pages: No need to change.
- Your domain, but not the same as landing page: You need a cross-domain solution.
- Third-party domain: This will not work in the long term, unless that third party is willing to implement sitewide tags.
Check if cookies are still available in conversion pages
To measure conversions accurately, the GCLIDs captured in first-party cookies on your landing pages must be available in the browser, as well as on your conversion pages. For this, cookies need to be available in the browser when a customer converts. Check with your developer team to make sure that cookies are not being deleted by your site before customers get to conversion pages. (You can use the Developer Tools to test conversions and check if the GCLID is attached to a cookie.)
Check if all of your conversions are flowing through a sitewide tag
If you have more than one conversion action, make sure that all of them are flowing through a sitewide tag. It could be that you are using a mix of old and new (gtag.js) conversion tracking, or that a domain uses a specific conversion tracking method that is not implemented in a linked account, but is implemented in the same account.
Check if all of your pages have a sitewide tag being fired
A sitewide tracking solution is needed on all landing pages to collect the GCLID and store it in a first-party cookie. If some landing pages don't contain a sitewide tag, clicks leading to them can't be tracked. To check which landing pages are being used in your ads, go to Reports > Reports > + (New Report) > Table and select Landing page as Row and Clicks as Metric, for the past 14 days. You can then use Google Tag Assistant to check for existing tags on those pages.
Don't fire conversion tracking from within an iFrame
Don't use existing (or 'piggybacking') tags (e.g. Floodlight tags or other tracking solutions) to deploy your conversion tracking tag. These tags will fire from another domain and so their deployed cookies won't be considered first-party cookies.
Make sure to check all these steps in all your sites (including mobile site/s)
If your Google Ads campaigns are sending traffic to different site domains and/or you have mobile versions of those sites, it's important to install sitewide tags correctly across each of those sites. Also, make sure that you check all the steps described in this article to ensure all conversions are being measured accurately.