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Campaign Tracking
What Is UTM Source?
UTM source identifies the specific platform, publisher, list, partner, or referrer that sent campaign traffic.
Updated 2026-06-17
Quick Definition
UTM source identifies the specific platform, publisher, list, partner, or referrer that sent campaign traffic.
Expanded explanation
utm_source names the platform, publisher, partner, list, or source that sent traffic to a destination URL.
Why it matters
Source values drive acquisition reporting and help teams compare performance by platform or partner. Poor source naming creates duplicate rows, weak attribution, and unreliable channel analysis.
Common mistakes
- Using campaign names as source values, such as utm_source=spring_sale instead of utm_campaign=spring_sale.
- Using both facebook and meta for the same source without a standard.
- Putting channel types like email, cpc, or paid_social in source instead of medium.
Examples
utm_source=google
utm_source=newsletter
utm_source=facebook
Practical example
For a LinkedIn ad, use utm_source=linkedin and utm_medium=paid_social rather than utm_source=q3_demo_campaign. The campaign name belongs in utm_campaign.