UTM parameters
Utm, Attribution, Analytics
Tags appended to a URL (source, medium, campaign, and more) that tell analytics tools where a visitor came from.
UTM parameters are tags added to the end of a URL that identify where a click came from. The five standard ones are utm_source (where, e.g. a newsletter), utm_medium (the channel type, e.g. email), utm_campaign (the specific campaign), and the optional utm_term and utm_content. When someone clicks a UTM-tagged link, those values pass through to your analytics, so you can attribute the visit - and any resulting conversion - to the right source.
For forms and lead funnels, UTMs are how you know which campaign produced which lead. Capturing them as hidden fields on the form means the source travels with the submission into your inbox, exports, and webhooks, so attribution is built into the data rather than reconstructed later.
UTMs are distinct from ad-platform click IDs (used by server-side conversion tracking); the two are often captured together for complete attribution. The funnels guide covers attribution end to end.