Facebook Pixel bemused with disparity in campaign data

New Member
2 0 1

Hi all,

Having some issues with FB ads and conversion tracking against Shopify, GA and Facebook.

We ran a campaign for a client, spent £1,024.28 over the course of 31 days from 1st October to the 31st.

Facebook Ads seems to think we generated a total of £37,838.94 from the campaign with 694 purchases. The product within the campaign was £89.99, if every purchase was for that one product, we'd be looking around £62,453.06. But obviously not everyone would purchase that one product from that one campaign - some browse and buy something else.


We had UTMs on the ads so we could obviously attribute the revenue to a specific campaign, however, when we review the campaign over the same date-range in Shopify, using the specific UTM parameters set on the Ad URL, Shopify seems to think that we’ve only made £241.99 total sales.

(I've had to remove some UTM information specific to the company)


I am completely dumbfounded as to how such a disparity in data can happen? The UTM string on the ad is as follows:


Google Analytics can't even track the UTMs from that date range - they don't even exist according to Google, however when I've done test UTMs direct to the site, they can be picked up via GA.

My first assumption was duplicate Pixels on the site, so I troubleshooted via the Pixel Helper and there's only 1 pixel existent on the site. 

My second assumption was that UTM codes weren't being saved as cookies, this is also false and I can see that the UTMs are being set for my test, along with the Shopify cookie: _shopify_sa_p

I believe the cookie _shopify_sa_p is used by Shopify to add referrals to orders? Please correct me if I'm wrong. I can see that the cookie expires after a time limit, could that possibly be a reason why? Also, if the cookie isn't set on the thank_you page, would that also cause Shopify not to attribute referral data to a campaign?


Previous Pixel setups have been via the built-in Shopify Facebook Pixel setup, I switched this around once we discovered the issue and are now testing using a Checkout Script which fires an event on purchase. This seems to be working for organic purchases, but as soon as we enable Ad campaigns, the data goes crazy again.

Would Facebook's integrated browser cause issues with campaign tracking?

I'm at a complete loss with this and have no idea what's causing the issues at this point.

Would there be something I've completely overlooked which could be causing this to happen?

It's also worth noting that this is happening on every single Facebook campaign we run. 

Any help would be greatly appreciated.

Many thanks


Replies 4 (4)
3 0 1

Recently, we are seeing wildly inaccurate data from our Pixel as well!

If you go and look at the actual purchase events and try to match them to real Shopify purchases, the relationship is hard to distinguish.

For example, sometimes the Pixel is reporting purchases that didn't happen. Other times, it's reporting the value of a purchase incorrectly.

We've also texted with our Pixel Helper and found nothing. We've even tried disabling the pixel inherent with Shopify and ONLY using Facebook App pixel.

Of course, Facebook support is nowhere to be seen and absolutely useless, so we're left to figure this problem out again on our own.

November 6th, we had Facebook pixel reporting 51,000$ in purchases from 2 orders... This is on a store with a 60-80$ AoV depending on the time of year.

New Member
2 0 1

Very strange indeed. We are currently scouring through the source files on the website to check for duplicate pixels as the pixel helper does not identify duplicates when I've tested. It's very strange. We're trying campaigns with more accurate UTMs to try and see if that can cause any attribution problems. My next steps will probably be manually firing a purchase event only when a UTM parameter is set as a cookie in Shopify. 

3 0 1

I still think there is some issue on Facebook's end.

Their support is useless though.

3 0 1

No updates still here huh?

I'm about to build completely custom FB Pixel events.