GA cookie data passed cross-domain from a form submission?

Question

Hello fellow webmasters,

So I have successfully set up cross domain tracking using tag manager and getting the unique clientId cookie data to be passed via URL parameter and seeing users convert in a funnel, fun stuff!

I have to implement this to a few sites, first of all, the site I got this working on referred to the second domain name with a regular <a> link.

Here is the tricky part where one of you might be able to help. The other sites I'm implementing this in have opt-in forms which after you submit then refer you to the second domain using InfusionSoft's email system. Because of this, Google's tag manager is not passing the _GA cookie data in the URL therefore creating a brand new session. Which causes my goal funnel to not convert through the steps.

Any idea or input on how this could be solved simply, without creating a second landing page after opt-in with a button telling users to click?

Answer 1

Google Tag Manager has an option to "decorate forms". You can find it under your pageview tag: More Settings -> Cross Domain Tracking -> Decorate Forms. Set that to true and GTM will send the GA cookie along to where the form submits to. If you have additional redirects after that, it'll be more difficult. What do you mean by this:

after you submit then refer you to the second domain using InfusionSoft's email system

Does the form submit launch an email client? If it is just a contact form that submits to the secondary domain (while also sending the email), the Decorate Forms option should work fine. Just make sure that the usual suspects Referral Exclusion List -> Add secondary domain and GTM's Auto Link Domains -> secondary domain are taken care of.