UTM & GA4 Tracking Glossary
Factual, concise definitions for marketing attribution.
utm_source
Definition: Identifies the specific advertiser, site, or publication that is sending traffic to your property (e.g., Google, Facebook, newsletter).
Requirement: Mandatory. Without `utm_source`, GA4 cannot attribute the session.
Best Practice: Always use lowercase (e.g., google, not Google). Keep it simple and representing the platform itself, not the ad format.
utm_medium
Definition: Identifies the advertising or marketing medium (e.g., cpc, banner, email).
Requirement: Recommended. Critical for GA4 Default Channel Grouping.
Best Practice: GA4 relies strictly on standard mediums to bucket traffic into "Paid Social", "Paid Search", etc. Use exact matches like cpc, email, or organic.
utm_campaign
Definition: Identifies the specific product promotion or strategic campaign (e.g., spring_sale, retargeting_30d).
Requirement: Recommended.
Best Practice: Establish a naming convention in your organization (e.g., Date-Geo-Product). Use underscores _ or hyphens - instead of spaces.
utm_term
Definition: Identifies paid search keywords.
Requirement: Optional.
Best Practice: If you use Google Ads auto-tagging (GCLID), you do not need to manually set `utm_term`. For Bing Ads or manual search campaigns, use this for the exact keyword targeted.
utm_content
Definition: Differentiates similar content, or links within the same ad. Used heavily for A/B testing.
Requirement: Optional.
Best Practice: Use this to specify creative sizes (e.g., 300x250), button colors (e.g., blue_cta), or ad copy variations.