If you sell online, and you use Mailchimp as your main email marketing method, then unless you take a few steps, your ability to track the results of your marketing mailings will be limited to the number of opens and the number of clicks on the links in your email. It does this by rewriting the links that you include in your mailing to redirect them via its own website. So, for example, if you include a button on your website linking to :
https://example.com
then when the email arrives in the recipient's inbox, the link will have been changed to :
https://exampledotcom.us4.list-manage.com/track/click?u=e6b884780ccada34209XXX&id=6d5be4XXX&e=821350XXX
When the user clicks on the email, they are first taken to the Mailchimp website, and thence onwards to the link that you wanted.
The fact that they go to the Mailchimp website first is what allows Mailchimp to track the click - that's how you can then go into the post-mailing report and see who has clicked on which links in your email, and how many times.
Once that's been logged by Mailchimp - which is practically instantaneous - they're sent on to the link you originally entered, but with a couple of URL parameters added - they're the bits after the question mark :
https://example.com?mc_cid=cebd31XXX&mc_eid=821350XXX
The two parameters are mc_cid, which is the Mailchimp Campaign ID, and mc_eid which is the Mailchimp Email ID - between them this links to the specific recipient on the specific campaign.
But for those to be useful beyond that point, your site has to be linked to Mailchimp via a slightly more in-depth method.
Linking your store
If your store runs on a platform such as Magento 2, Wordpress / Woocommerce or Shopify then you can link it to Mailchimp - either via the official extension / plugin, or via the API.
If the user arrives via the Mailchimp-tagged link, then the mc_cid and mc_eid values are stored in a cookie. Once the user completes checkout, the information on their purchases is fed back to Mailchimp via those values, which in turn allows Mailchimp display the e-commerce revenue for the campaign.
How good is Mailchimp's tracking, though?
It's somewhat limited, if we're brutally honest. If you've linked your store, then you may well start seeing some revenue information - but it's somewhat inconsistent, and somewhat lacking. For example, on the campaigns page the "Revenue" summary may display at £0 even if, on clicking into the report and onto the e-commerce tab, you're actually shown conversions.
More problematically, the e-commerce report is bare bones, at best. At the moment the relevant tab says that Mailchimp are improving this, and "[i]n the meantime, the most accurate order and revenue data can be found on the overview tab", but frequently the overview tab doesn't actually display any order or revenue data.
The e-commerce tab gives a total number of orders, total revenue, and average order revenue (total revenue divided by number of orders) but that's it - no detail on who bought what. To compound things, below the summary Mailchimp may well be telling you that if you connect your store you'll get more information when, actually, your store is already connected. Not the sort of consistency we have come from Mailchimp over the years.
So, how can we improve on that?
The simpler answer is to ignore Mailchimp's ecommerce reporting. Assuming you have correctly set up ecommerce tracking in Google Analytics - so that it's tracking what products are ordered as part of each sale - then it's a relatively simple process.
The first step is to link Google Analytics and Mailchimp via the Integrations tab - this is a simple process that Mailchimp walks you through.
Then what we need to do is to use UTM parameters. These are tags which are added to URLs - to indicate the source, the medium and the campaign of a visitor - which can then be filtered in Google Analytics reports. So for a marketing newsletter sent via Mailchimp, the utm_source would be Mailchimp, the utm_email would be Email, and the utm_campaign would be the campaign in question.
Because it's always going to be Mailchimp, and always going to be sent via email, then it's only the campaign that we need to specify each time.
When creating or duplicating a campaign, if you scroll down to the Settings and Tracking section of the campaign, and expand that, you'll see - assuming you've linked Google Analytics and Mailchimp - the option to tick the "Google Analytics link tracking" box and below that a textbox where you can specify the title of the email (it'll put in the existing title of the mailing, but you can change that if you wish).
And that's it - Mailchimp will still redirect clicks through its own website, initially, and still add its own mc_cid and mc_eid tracking parameters, but will also add the three UTM tracking parameters. You will then be able to filter your e-commerce reporting in Google Analytics to only show conversions from a specific campaign.
It's good, but it's still not perfect
The issue with any Google Analytics data is that it will be skewed downwards by those who block trackers (either through their choice of browser or through browser extensions).
To compensate for that, you can extrapolate that out (by assuming that anything between 10% and 30% of visitors will be blocking trackers.
Alternatively, your chosen e-commerce platform may track sales by source either out of the box (as Shopify does) or through a third party module (which Magento 2 would require).
If it's essential that you have completely accurate information, then server-side tracking via something like Plausible or Fathom may be an option - these are standalone solutions, rather than sending through information to Google Analytics, but it would also be possible to create a module within Magento 2 which works server-side and sends data to Google Analytics via its API, thus avoiding the issue with trackers being blocked on the user's side.
Effective revenue tracking relies on a solid Analytics setup — we covered the fundamentals in Master Google Analytics: Essential Insights for SMBs.
Not sure if Google Analytics is even set up on your site? Check out Day 6 of our 10 Days to a Healthier Website series.