Google analytics and Adwords showing very different figures

Question

In AdWords I have 1 advert running only. The landing page includes a querystring so I can track it. EG, www.mydomain.com/products?source=CPC

I also use Google Analytics.

For February I have approx 1450 clicks in AdWords. This means, 1450 went to my website.

In Google Analytics, according to my landing page, there were only ~850 visits.

In Google Analytics, in the Acquisition -> All traffic page, it suggests that Google CPC brought 517 visits...

I know tracking tools are not 100% reliable but this figure seems to be showing something is very wrong.

How can I tell which of the figures is accurate or is this just a limitation of reporting tools?

Answer 1

Your landing URL from your campaign is not ideal for Google Analytics tracking. I would recommend using the Google Analytics URL builder to add parameters to the URL. Specifically source=CPC would become utm_source=CPC. Google Analytics also likes it when you have other fields like the campaign name.

When this tracking is in place, your campaign traffic will show up under "Acquisition -> Campaigns". This allows you to see stats on just the paid traffic easily in one spot. It also allows you to see how that traffic performed against goals that you define such as "how many signed up?" or "how much did they spend?"

Alternately, Google AdWords now has an auto tagging feature that will assign all the values and pass them to Google Analytics based on which campaign items are in within Google AdWords.

Answer 2

I phoned Google AdWords. They were certain the number shown in AdWords is accurate, and explained because it's related to a payable service, it HAD to be accurate. There is no direct contact he could give me for Analytics but, he suggested the fault was there.