UTM Parameters and GA4 Channels
What are UTM parameters?
UTM parameters are five standard tags appended to a URL's query string:
| Parameter | Purpose | Example |
|---|---|---|
utm_source | The platform or site the link runs on | google, newsletter |
utm_medium | The marketing channel | cpc, email |
utm_campaign | The campaign or promotion name | spring-launch |
utm_term | The paid keyword (optional) | running-shoes |
utm_content | The creative variant (optional) | banner-a |
Your analytics tool reads them on every visit and attributes the session to a campaign and a channel.
Why sessions land in "Unassigned"
GA4 assigns each session to a default channel by matching source and medium against fixed rules. When nothing matches, the session lands in Unassigned, where channel reports never show it.
The three most common causes:
- Unrecognized medium. GA4 knows
email, notNewsletter,mailorE-Mail-Kampagne. A creative medium value files the whole campaign under Unassigned. - Capitalization. GA4 is case-sensitive:
Emailandemailare different values. One capital letter splits your report rows or breaks channel matching entirely. - Swapped fields.
utm_source=cpc&utm_medium=facebookputs the channel word in the wrong slot; the rules only matchutm_source=facebook&utm_medium=cpc.
Medium values that map to real GA4 channels
| Medium | GA4 channel |
|---|---|
cpc, ppc | Paid Search / Paid Social / Paid Shopping / Paid Video, decided by the source |
paid-social | Paid Social |
display, banner, cpm | Display |
email, e-mail | |
social, social-media | Organic Social |
affiliate | Affiliates |
referral | Referral |
video | Organic Video |
audio | Audio |
sms | SMS |
push | Mobile Push Notifications |
For paid mediums the source decides the exact channel: google + cpc is Paid Search, facebook + cpc is Paid Social.
Naming rules that keep reports clean
- Lowercase everywhere. Decide once, then never think about it again.
- One separator. Pick hyphens or underscores for multi-word values and stay with it:
spring-launch, notSpring Launch. - One spelling per platform.
facebook,fbandFacebookbecome three different sources in your reports. Fix one spelling per platform. - No personal data. Campaign parameters end up in server logs and analytics tools; never put email addresses or names in them.
How Snipzr helps
The Snipzr link builder checks every source and medium combination against these rules while you type and shows the resulting GA4 channel, or a warning before a link that would land in Unassigned ever ships. Try it in the link dialog or use the free standalone builder without an account.