How to use UTM parameters with Google Analytics 4

Where UTM visits appear in GA4

Open Reports, then Acquisition, then Traffic acquisition. The default table groups sessions by channel. Change the primary dimension to Session source / medium or Session campaign to see your tags exactly as you wrote them.

Visits appear in the Realtime report within seconds, which makes it the quickest way to test a new link: click it yourself and look for your source.

How utm_medium decides the channel

GA4 sorts sessions into default channels using mostly the medium:

• email (or e-mail) → Email
• social, social-network, social-media or sm → Organic Social
• cpc or ppc together with a search source → Paid Search
• referral → Referral
• affiliate → Affiliates
• anything it doesn't recognise, such as print, qr or flyer → Unassigned

Fixing Unassigned traffic from QR codes and print

Unassigned isn't lost data. The sessions still carry your source and campaign. You have two options. Use a recognised medium (for example utm_medium=referral with utm_source=flyer). Or keep a clear medium like qr and add a custom channel group in GA4 under Admin, then Data display, then Channel groups.

A naming system that survives

• Lowercase everything. GA4 treats Instagram and instagram as different sources.
• Hyphens, not spaces: spring-sale, not Spring Sale.
• Source is the place, medium is the type, campaign is the reason.
• Keep a shared list of allowed values and reuse it.
• Never tag internal links on your own site. It starts a new session and overwrites the real source.

Keep tagged links short

A fully tagged URL is long and ugly in a caption or on print. Put the tags on a short link: the redirect adds them on the way through, and you can correct a typo after the link is out.