Is there a way to track conversions that came from emails?
For example, If I send an email contains a link to a form, once the person fills out the form he is transferred to an external payment page (PayPal for example) and then pay.
Is there a way, via Marketo only, without additional platforms or tools (UTM), to track people who opened the email and eventually converted (in this case, pay)?
If not, what are your solutions for these kinds of situations?
How does Marketo know that the person paid?
Does PayPal or another tool flag the person as Paid=T? That would be the only other way than to create a full tracking.
Smart List: Paid and Clicked Link in Email X with date range.
Now, there are some other methods using Marketo Programs, RCE, and attribution to make a Clicked Link In Email a Status or Success and then to give it MT attribution.
Here's a few discussion threads that somewhat relate: Can you accept payment through a Marketo form? ; PayPal , but it sounds like you just want to point people to an external payment page on your company's website.
If you want to avoid using webhooks and the custom integration, then like Josh said how will Marketo know that the person converted?
Have you thought about using Google Analytics? You'd just need to drop the snippet of JS tracking code onto the webpage, and Google Analytics will collect any transactional/eCommerce related data. Attributing the purchase to a specific email campaign should work if you're using UTM parameters.