Hi Shelby,
There are key advantages to both UTMs and Reference IDs. UTM are powerful, allowing you to track multiple campaigns and sources to one one registration, however they are usually a little harder to implement but they have the benefit of also being compatible with embedded registration by pulling the UTM from the parent site. Reference IDs are easy to implement, you create a Cvent weblink and in the UI add a reference ID, however because these are a Cvent standard only, they are not compatible with embedded registration on your external website outside of just one reference ID associated to the widget itself.
For more details, please reach out to your account team so you may have a strategic discussion with one of our product experts.
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Carl Robinson
Senior Solutions Specialist
Cvent
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