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UTM tracking

UTM tracking in Mixpanel

Mixpanel's JavaScript SDK automatically captures the five standard UTM parameters from the page URL and stores them as properties on tracked events, and can persist the first values as user profile properties. This makes UTM the basis for acquisition-channel breakdowns in Mixpanel without extra instrumentation, provided you understand when the values are read and how they persist.

Verified against primary sources

How Mixpanel reads UTM

Mixpanel's web SDK parses the current page URL for the five standard UTM parameters and attaches them as properties on events tracked from that page. By default it can also save the first-seen values to the user profile (often labelled initial utm_source and similar), so you can attribute a later conversion to the channel that first brought the user.

The parsing happens client-side at the moment the SDK initialises on a page. If a redirect or a privacy tool removes the query string before the SDK runs, Mixpanel sees no UTM values for that load.

Reading campaign attribution

In Insights, Funnels, or Flows, group or filter by utm_source, utm_medium, or utm_campaign to see how each channel performs. Using the first-touch user properties for the breakdown attributes downstream events to the original acquisition channel rather than the page where the event happened to fire.

Keep your UTM values lowercase and consistent. Mixpanel treats Newsletter and newsletter as distinct property values, so casing drift fragments a single channel across multiple rows.

How it appears in analytics and logs

When a Mixpanel event shows populated utm_source and utm_medium properties, the visitor arrived on a tagged URL and the SDK read it on that page load. Empty UTM properties mean the landing URL had no parameters, the values were stripped before the SDK ran, or the session began on an untagged page.

Diagnostic use case

Break down Mixpanel events or funnels by acquisition channel, and confirm that incoming campaign links carry UTM values into Mixpanel's utm_source / utm_medium / utm_campaign properties.

What WebmasterID can help detect

WebmasterID records the inbound campaign hit server-side, independent of whether Mixpanel's client SDK fired, so you can reconcile tagged arrivals against Mixpanel events and spot links that lost their UTM before the SDK read them.

Common mistakes

Privacy and accuracy notes

UTM values describe the campaign, not the person. Treat them as campaign metadata in Mixpanel and avoid placing names, emails, or any personal data in UTM parameters, since they are stored as plain event properties and can appear in exports.

Frequently asked questions

Does Mixpanel capture UTM automatically?
The web SDK reads the five standard UTM parameters from the page URL and attaches them to events, and can persist the first-seen values to the user profile. No custom code is required for the standard parameters.

Related pages

Sources and verification notes

Last reviewed 2026-06-24. Facts are checked against primary/official sources where available; uncertain specifics are marked “Data not yet verified” rather than guessed.