Unique identifier for affiliate marketing



We are working with different affiliate partners, they send traffic to our pages and thus generating new leads/ contacts.
When it comes to attribution (that’s important to pay them), it gets hard to know which lead was generated by which affiliate.

Is there a possibility for hubspot to send a “unique identifier” such as the email address, back to the affiliate? That way, we would be able to compare the contacts and thus only pay for the leads that were actually generated via that affiliate.


Hi @AnneliesV,

Just to make sure that we’re on the same page, are you looking to attribute specific site visitors to these affiliate partners, or visitors that convert and become contacts? If you’re looking to track visitors associated with affiliate partners, it’s best to use sources reporting and tracking URLs, per the following Knowledge Base article:


Hello Derek,
Indeed, we want to know which contacts converted (filled out the form on the LP) via which partner. We currently use the URM_source, UTM_medium and UTM_campaign parameters to supply hubspot with more information on the source of the contact, but we still see a difference in the number of leads generated.
When we check the platform of the affiliate partner, we see more leads/contacts than we see in hubspot.
In order to better link the two, I would like the affiliate to actually see the email address of the lead (as the unique identifier). This way, we would be able to compare the leads/contact 1:1.
I hope you understand our problem, and am looking forward to your reply!
Greetings, Annelies


Hi @AnneliesV,

The original source properties (as set by the UTM parameters) are unlikely to ever match 1:1 with the contacts created via the form, since it’s possible that a contact that converted via a partner would have an original source other than that partner (see this Knowledge Base article). If you’re tracking contacts that convert on forms, it’d likely be better to add a hidden field to the form submission to track which partner the contacts converted with.


Hi Derek,

Thank you for your reply!

Indeed, I was already aware of that. We have integrated hidden fields in all of our forms, for the “utm_source”, “utm_campaign” and "utm_medium.
We provide those parameters in all of our target URL’s, so that these fields are being filled out whenever a contact enters hubspot via such a partner (or other network we like to track).
Even with these parameters, we see that there are conversions in the platform of our affiliate partner that are not visible in our hubspot contacts.
So basically I am looking for a way to send the emailaddress of the filled out form back to the affiliate partner, so that we can compare them 1:1

I hope you this extra input gives you an idea of how to solve our issue, since this is an issue we have been struggling with for over a year now …
With the start of hubspot, we were told that this problem would disappear, but we still need to find the solution for it.

Thank you for your input,


Hi @AnneliesV,

How are you looking to send the lead email address back to your partners? You could create a workflow to send a notification email to a partner when a lead comes in from them, or to trigger a webhook. I’m not sure exactly how you’re looking to send the email address to the partner, but there are a number of different options using workflows or the forms API.


Hello Derek,

I was hoping you or someone else on the forum would know how to do this.
Our affiliate partner, Trade Tracker, has a platform where we can login and see the leads that are coming in. Currently, we only see the date and time, affiliate partner how this lead entered. So there I would like to see the emailaddress of the lead, so we can compare 1:1

They are using a pixel / code in which it is being programmed that the email address will end up in this online platform automatically.
I was hoping you would know how to do this, using hubspot as CRM?



Hi @AnneliesV,

I’m unfamiliar with how exactly Trade Tracker collects this lead information, so I can only speak to the HubSpot side of this topic. The ability to view a lead’s email address in this platform depends entirely on how they gather the lead information; the email address of a contact can be pulled via the Contacts API, or potentially by using a custom form and the Forms API. As far as ‘sending’ this information is concerned, the only way I can imagine that working is by using a custom form, and sending the information along to Trade Tracker at the time of form submission. I’ve attached some documentation for these APIs below, and if you have any specific questions with regard to them, let me know. I’d recommend reaching out to Trade Tracker support for some more details on their system, as well.