Deep Link Doctor
Home / Link problems

Traffic lands in the wrong channel or Unassigned

GA4 sorts traffic into channels by utm_medium. See which medium values land in Paid Social, Email or Affiliates, and why other values end up in Unassigned.

SymptomPaid campaign traffic shows as Organic Social, Referral or Unassigned instead of a paid channel.
Likely causeThe utm_medium value doesn't match the rule for the channel you expected, such as social instead of paid_social.
FixUse a medium that matches Google's channel rules, such as cpc or paid_social for paid ads and email for email.

Short answer: Google Analytics 4 groups visits into channels using rules based mostly on utm_medium. Paid channels need a medium such as cpc, ppc, retargeting or anything starting with paid. A medium of social goes to Organic Social, and a medium that matches no rule goes to Unassigned.

What is a default channel group?

Default channel group: Google Analytics 4's fixed set of rules that sorts every visit into a channel, such as Paid Social, Email or Organic Search, using its source and medium.

Google says these rules "aren't case sensitive and can't be edited". You can't teach them a new medium, so your links have to match them.

Which utm_medium values does GA4 recognise?

Paid channels share one rule: the medium must match cpc, ppc, retargeting, or anything containing "cp" or starting with "paid". Other channels use these mediums:

ChannelMedium that matches
Paid Social, Paid Search, Paid VideoA paid medium, plus a source on Google's social, search or video list
Paid OtherA paid medium with any other source
Displaydisplay, banner, expandable, interstitial or cpm
Organic Socialsocial, social-network, social-media, sm, or a social source
Emailemail, e-mail, e_mail or e mail (source or medium)
Affiliatesaffiliate
Referralreferral, app or link
SMSsms (source or medium)
Mobile Push Notificationsending in push, or containing mobile or notification
UnassignedAnything that matches no rule

Google lists other rules too, such as Audio, Cross-network and the shopping channels. Traffic from Google Ads and other Google platforms is classified by platform settings, not by these rules.

Example

Paid Instagram ads tagged with social land in Organic Social:

https://example.com/sale?utm_source=instagram&utm_medium=social&utm_campaign=diwali_sale

A paid medium sends them to Paid Social, because Instagram is a social source:

https://example.com/sale?utm_source=instagram&utm_medium=paid_social&utm_campaign=diwali_sale

An influencer campaign tagged utm_medium=influencer matches no rule, so it ends up in Unassigned. If the creator is paid, use paid_influencer to keep it in a paid channel. If not, referral or social keeps it out of Unassigned.

How to fix it

  1. Paste the link into the link checker. It notes when a medium doesn't match a standard channel.
  2. For paid ads, use cpc, paid_social or another value starting with paid.
  3. For unpaid posts, use social. For newsletters, use email. For partners, use affiliate or referral.
  4. Keep the medium lowercase anyway. Channel rules ignore case, but medium reports don't. See inconsistent UTM naming.
  5. Add the agreed mediums to your naming sheet and build links in the UTM builder, which suggests standard values.
Related

Related problems

UTM The same UTM tag appears twice in a linkA link with two utm_source or utm_campaign values gives reports a choice, and you can't be sure which one they keep.UTM Campaign link is missing UTM tagsWithout utm_source, utm_medium and utm_campaign, visits show as direct, referral or (not set) instead of your campaign.UTM UTM values are written differently across linksInstagram, instagram and insta are three different sources to an analytics tool, so one channel ends up split across several rows.

Check a link →

FAQ

Common questions

Why is my paid social traffic showing as Organic Social?

Most likely the medium is `social`. Google's rules send `social` to Organic Social, so paid ads need a paid medium such as `paid_social` or `cpc`.

What does Unassigned mean in GA4?

It's the channel Google uses when no rule matches the visit's source and medium. An unusual medium, such as `influencer` or `story`, is the usual cause.

Is utm_medium case-sensitive for channels?

No. Google says channel definitions aren't case sensitive. The medium report still shows `Email` and `email` as separate rows, so lowercase is still the right habit.

Can I add my own channel rules?

Google says the default channel group can't be edited. Match your mediums to its rules instead, so every report agrees.

What are UTM parameters?

UTM parameters are tags added to the end of a link, such as utm_source and utm_campaign, that tell analytics tools where a visit came from. They let you see which campaign, channel and ad brought each visitor.

Which UTM parameters are required?

Use utm_source, utm_medium and utm_campaign on every campaign link. utm_term and utm_content are optional and help you compare keywords or ad variants.