A tag added to a URL's query string that tells your analytics tool where a visitor came from. There are five standard ones, all prefixed utm_. They're just text you append after a ?, e.g. ?utm_source=google&utm_medium=cpc.
The specific origin of the click — the platform or property it came from. Examples: google, facebook, linkedin, newsletter. Source answers "which specific place?"
The marketing channel type. Examples: cpc (paid search), email, paid-social, organic-social, display, affiliate, referral. GA4 uses this field to bucket traffic into default channel groups, so keeping it to a short fixed list matters.
The name of the specific campaign a link belongs to. Best given a structured pattern like region_quarter_initiative_type (e.g. na_q3_summersale_promo) so you can filter and roll up campaigns later.
The paid keyword tied to a link, used mainly in paid search. Many teams make it required whenever the medium is paid, so every paid click stays attributable.
The creative or A/B variant of a link — e.g. hero-a vs hero-b. Optional, but useful for testing which version drove results.
The controlled list of allowed values for each UTM field. A taxonomy is what turns "type anything" into "pick from an approved set," which is the foundation of consistent data.
A required structure for campaign names, such as region_quarter_initiative_type. It keeps every campaign name the same shape so reporting can group them reliably.
The practice of defining an allowed taxonomy and naming pattern, then enforcing them for everyone who builds links — so off-spec links are blocked at creation, not discovered later. See what UTM governance is.
A UTM link that violates your taxonomy or naming pattern — wrong casing, a made-up medium, a malformed campaign name. Off-spec links are what fragment your analytics.
The percentage of your links that match your spec. Tagsmith's audit computes this so you can see how clean your back-catalog is at a glance.
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