When to not do cross-domain tracking


Cross-domain tracking is great.  But just because you can do something doesn’t always mean you should.  This goes for cross-domain tracking as well.  Sometimes tracking two domains as separate sites instead of together, may be the right approach.

While there is no hard-and-fast way to make this decision (that I know of), here are a couple things to consider.

*Can visitors be commonly expected to cross from one domain to another to accomplish your goals?  Their goals?
*Do the domains serve different audiences?

Imagine, for example, pbs.org and pbskids.org.  These two sites (usually) serve very different audiences. And someone would not normally be required to cross from one domain to the other in order to accomplish their goal.  This situation is probably best served by tracking them as different sites without any cross-domain tracking.

Another example is a company such as Perillo Tours that sells vacation tours.  There is one domain that is the consumer facing site (perillotours.com)– you and I can buy a tour on this domain.  The other domain is for travel agents to purchase tours for their customers (perilloagents.com).  Both sites are virtually identical (they provide almost the exact same functionality, after all).  Although you can move between sites, the two domains are serving different audiences and the visitors would not need to cross domains in order to accomplish goals. This is another example of when you’d not want to use cross domain tracking.

Again, these are just a couple examples and some things to think about when trying to decide if you want to implement cross-domain tracking. It may not apply to most of you, but for those in a situation like this, I hope it helps get you thinking about how to implement GA for your domains.


John is a former LunaMetrician and contributor to our blog.

  • Hi John,
    Good post. I actually had problem with GA on my site when I implemented cross domain tracking. Content report started to do some weird stuff, and I realized I could not do any site overlay report, which I think is the best report EVER. The sacrifice was too big for just the cross domain tracking “add-on”, and I decided to get rid of it in order to get my site overlay report back. I read in a forum that people were having the same problem: concretely, the site overlay report is 100% NOT POSSIBLE if you have cross-domain tracking, so I would actually advice to leave it…

  • The site overlay report is based on matching the URLs that GA has, with the URLs for the links on the webpage.

    When we do cross-domain tracking, we might end up with an /index.html on the first domain, AND an /index.html on the second domain. For purposes of the Site Overlay report, GA does not know the difference. If you have 1 click to the first one, and 1 click to the second one, GA simply sees 2 clicks to /index.html and reflects this in the Site Overlay. This is usually what messes up the site overlay report in GA. However, there are Lots of things that can go wrong with the site overlay report.

    If you like the site overlay report, you might like trying out Heat Mapping analytics, such as Crazy Egg. Software like this shows you where a visitor clicks on your page, even when it’s not a link, and doesn’t depend on matching URLs.

  • I wouldn’t say “mess up”. There is nothing “wrong” with either way to do it, but each way will give you different numbers. In either case, the numbers will be “right” but just defined differently.

    When you have 2 domains that serve completely different audiences, you really have 2 different websites, and even when looking at the data in aggregate, I think it makes more sense in most cases to track the sites as separate entities rather than doing Cross-Domain tracking to treat them as one site.

Contact Us.

Follow Us




We'll get back to you
in ONE business day.
Our Locations
THE FOUNDRY [map] LunaMetrics

24 S. 18th Street
Suite 100

Pittsburgh, PA 15203


4115 N. Ravenswood
Suite 101
Chicago, IL 60613


2100 Manchester Rd.
Building C, Suite 1750
Wheaton, IL 60187