What are UTM parameters?
UTM parameters are short tags added to the end of a link. When someone clicks, GA4 reads them and records exactly where the visit came from: which platform, which kind of traffic, which campaign and even which ad. Without them, a click from your Instagram bio or email newsletter often shows up as “Direct” or “Referral”, and you can’t tell which campaigns are actually driving sales.
| Parameter | What it answers | Example |
|---|---|---|
| utm_source | Where did the click come from? | facebook, google, newsletter |
| utm_medium | What type of traffic is it? | paid_social, cpc, email |
| utm_campaign | Which campaign? | black-friday-2026 |
| utm_id | Campaign ID (for data imports) | 12345 |
| utm_term | Which keyword or audience? | running-shoes, lookalike-1pct |
| utm_content | Which ad or link? | video-a, hero-button |
How GA4 uses your UTMs
GA4 sorts every session into a default channel group like Paid Search, Paid Social, Email or Organic Social, based mainly on source and medium. If your medium doesn’t match GA4’s rules, the session lands in Unassigned, the most common GA4 reporting headache. Safe values:
- Paid social: utm_medium=paid_social (or cpc) with a social source such as facebook, instagram or linkedin.
- Organic social: utm_medium=social.
- Email: utm_medium=email.
- Display: utm_medium=display or banner.
- Affiliates: utm_medium=affiliate.
UTM naming rules that save you later
- Always lowercase. GA4 is case-sensitive, so “Facebook” and “facebook” become two rows.
- Use hyphens, not spaces. Spaces turn into %20 and look messy in reports.
- Pick a convention and write it down. For example: campaign = offer-month-year, content = format-variant.
- Never tag internal links. UTMs on links within your own site restart the session and wipe out the real source.
- Keep Google Ads auto-tagging on. The gclid gives GA4 richer data than manual UTMs do.
Using dynamic parameters in Meta and Google Ads
Ad platforms can fill in UTM values automatically. The Meta Ads preset uses {{campaign.name}}, {{adset.name}} and {{ad.name}}, which Meta swaps for real names at click time. Paste the parameters into the ad’s URL parameters field. For Google Ads, ValueTrack parameters like {keyword} and {campaignid} go in the Final URL suffix. The builder leaves anything in braces untouched when cleaning values.
Frequently asked questions
What are UTM parameters?
Tags added to a URL (utm_source, utm_medium, utm_campaign, utm_term, utm_content, utm_id) that tell analytics tools like GA4 where a visitor came from.
Which UTM parameters does GA4 require?
Use at least utm_source, utm_medium and utm_campaign. GA4 uses source and medium to assign default channels.
Why does my UTM traffic show as Unassigned in GA4?
Usually because utm_medium doesn’t match GA4’s default channel rules. Use cpc, paid_social, email, social, display, referral or affiliate.
Should I use UTMs with Google Ads?
Keep auto-tagging on. GA4 reads the gclid automatically. Manual UTMs are optional and mainly help other analytics tools.
Are UTM parameters case sensitive?
Yes. GA4 shows “Facebook” and “facebook” as different sources, so always use lowercase.